【深入理解TcaplusDB技术】入门Tcaplus SQL Driver

简介

TcaplusDB SQL Driver/C++ 是用于连接C++应用程序到TcaplusDB服务器的TcaplusDBConnector。用于以传统方式使用SQL语句的TcaplusDB服务器。

二进制安装

TcaplusDB SQL Driver/C++二进制发行版是以特定于平台的压缩格式提供的。二进制发行版也以更通用的格式以压缩的tar文件或zip压缩包提供。 TcaplusDB SQL Driver/C++二进制发行版可用于几个平台，以压缩的tar文件或zip压缩包形式打包，在这里表示为PACKAGE.tar.gz或PACKAGE.zip. 要解压tar文件，在预期的安装目录中使用此命令： tar zxvf PACKAGE.tar.gz 从Zip压缩包安装(.zip)，使用WinZip或者其他可以读取“.zip"文件的工具，将文件解压缩到您选择的位置的文件。

TcaplusDB和Tcaplus SQL Driver版本的兼容性

• TcaplusDB版本： TcaplusDB SQL Driver/C++基于TcaplusDB 3.53.0开发。

• C++标准： TcaplusDB SQL Driver/C++基于C++98标准开发。

TcaplusDB SQL Driver/C++快速入门

通过TcaplusDB SQL Driver/C++连接TcaplusDB，链接格式如下： tcp://<instance_ip>:<instance_port>?app_id=<app_id>&zone_id=<zone_id> 其中<instance_ip>为实例主机ip；<instance_port>为开放端口，默认为9999；<app_id>为业务id，<zone_id>为游戏区id。 连接与读取数据示例：

#include "cppconn/statement.h"
#include "cppconn/resultset.h"
#include "cppconn/connection.h"
#include "cppconn/driver.h"
#include "cppconn/metadata.h"
#include "cppconn/resultset.h"
#include "cppconn/resultset_metadata.h"
#include "cppconn/prepared_statement.h"
#include "tcapsql_driver.h"
#include <iostream>
​
int main()
{
    sql::Driver *driver;
    sql::Connection *conn;
    sql::Statement *state;
    sql::ResultSet *rset;
    try {
    driver = sql::tcapsql::get_driver_instance();
    conn = driver->connect("tcp://192.168.0.1:9999?app_id=2&zone_id=3", "", "123456");
    state = conn->createStatement();
    rset = state->executeQuery("SELECT * FROM user WHERE user_id = '10000'");
    while (rset->next())
    {
        std::cout << rset->getString(1) << std::endl;
    }
    delete rset;
    delete state;
    delete conn;
    } catch (sql::SQLException &e) {
        std::cout << "catch errCode " << e.getErrorCode() << " errMsg " << e.what() << std::endl;
        return EXIT_FAILURE;
    }
    return 0;
}

Makefile

export TCAPSQL_DRIVER=/youpath/TcaplusSQLDriver3.53.1.204605.x86_64_release_20210521/release/x86_64/;
CPPFILE=$(wildcard *.cpp)
LIBS +=-L$(TCAPSQL_DRIVER)/lib -Wl,-Bstatic -ltcaplus_sqldriver -Wl,-Bdynamic -lpthread -lanl
 
INC = -I$(TCAPSQL_DRIVER)/include/
.PHONY: all clean 
all:
    g++ -o mytest $(CPPFILE) $(INC) ${LIBS}  
clean:
    rm -f mytest

TcaplusDB的表定义与表创建

使用xml定义TcaplusDB表，示例如下：

<?xml version="1.0" encoding="GBK" standalone="yes" ?>
<metalib name="demo_table" tagsetversion="1" version="1">
    <struct name="user" version="1" primarykey="user_id,server_id" splittablekey="user_id">
        <entry name="user_id" type="string" size="450" desc="用户ID"/>
        <entry name="server_id" type="uint64" desc="服务器ID" />
        <entry name="nick_name" type="string" size="50" desc="昵称"/>
        <entry name="desc" type="string" size="1024" desc="描述信息"/>
        <entry name="state" type="Tinyuint" defaultvalue="0" desc="用户状态 0 : AVALIABLE, 1 DELETED"/>
        <index name="index1" column="user_id"/>
        <index name="index2" column="user_id,server_id"/>
    </struct>
</metalib>

• 元素 metalib 是 xml 文件的根元素。

• 包含 primarykey 的 struct 元素是一个表，不包含 primarykey 的 struct 元素为一个普通结构体。

• 每次修改表结构时，版本属性值需要相应地加1，初始版本始终为1。

• primarykey 属性指定主键字段；对于 generic 表，您最多可以指定8个主键字段，对于 list 表，则可以指定7个。

• splittablekey 属性等效于分片键（shard key），TcaplusDB 表被拆分存储到多个存储节点。splittablekey 必须是主键字段之一，一个好的 splittablekey 应该具有高度分散性，这意味着值的范围很广，建议选用字符串类型。

• desc 属性包含当前元素的描述。

• entry 元素定义一个字段，支持的值类型包括 int32，string，char，int64，double，short 等。

• index 元素定义一个索引，该索引必须包含 splittablekey。由于可以使用主键查询表，因此索引不应与主键属性相同。

TcaplusDB SQL Driver/C++示例

TcaplusDB SQL Driver/C++：获取driver实例

通过调用 get_driver_instance 可以获取到driver实例，每个进程获取一次足矣。

sql::Driver * driver = sql::tcapsql::get_driver_instance();

使用后端TcaplusDB的连接信息生成 URL 并建立连接

// IP
#define DIR_HOST "192.168.0.1"
// port
#define DIR_PORT "9999"
// app_id
#define APP_ID 2
// zone_id
#define ZONE_ID 3
// signature
#define SIGNATURE "123456"
char url[120] = {0};
snprintf(url, 120, "tcp://%s:%d?app_id=%d&zone_id=%d", DIR_HOST, DIR_PORT , APP_ID, ZONE_ID);
// 中间参数为收发线程的线程名，conn的收发线程名相同，说明使用同一个收发线程收发包。
// 1个收发线程可以处理大概200个conn的请求响应。不过conn越多会造成延时变高，按需调整。
sql::Connection * conn = driver->connect(url, "instance1", SIGNATURE);
​

Statement 对象可以执行基本SQL查询，并通过 ResultSet 类获取结果。 对从 driver.connect() 获取的 Connection 对象调用 createStatement() 方法，则可创建一个 Statement 实例，之后就可以通过调用 executeQuery(String) 方法使用SQL语句执行SELECT查询。 如果要更新数据库中的数据，可以使用 executeUpdate(String SQL) 方法。 当语句是SELECT时，可以通过调用 getResultSet() 方法获取查询结果。当语句是UPDATE，INSERT，DELETE时，可以通过对 Statement 实例调用 getUpdateCount() 获取受影响的行数。 以下是执行SELECT查询的示例：

sql::Statement * state = conn->createStatement();
sql::ResultSet * rset = state->executeQuery("SELECT * FROM user WHERE user_id = '10000'");
while (rset->next())
{
    std::cout << rset->getString(1) << std::endl;
}
delete rset;
delete state;

sql类型和TcaplusDB类型对应关系

**TcaplusDB和sql数据类型对应关系

将TcaplusDB错误码映射到SQL Driver SQLState代码

TcaplusDB部分常见错误码及说明如下：

已知问题和SQL局限性

SQL语法的限制

假设数据表demo共有六个字段：key1,key2,key3,value1,value2，其中，key1,key2为partkey，key1,key2,key3组成fullkey。

插入操作

插入操作必须显示指定所有字段的值，除非在表定义中指定了其默认值。 插入单条记录的SQL语句形式如下： INSERT INTO demo (key1,key2,key3,value1,value2) values (x1,x2,x3,x4,x5); 插入多条记录的SQL语句形式如下： INSERT INTO demo (key1,key2,key3,value1,value2) values (x1,x2,x3,x4,x5); INSERT INTO demo (key1,key2,key3,value1,value2) values (x6,x7,x8,x9,x10); ### where子句语法限制

在未配置全局索引的情况下，where子句中的过滤字段由两部分组成：1、必选部分：partkey或fullkey；2、可选部分：过滤条件。 partkey或fullkey：只能进行等值查询，且组成partkey或fullkey的各个字段之间只能用AND连接； 过滤条件：支持NOT、=、>、<、!=、>=、<=运算符，且多个过滤条件之间可以用AND或OR连接，支持key字段或value字段。 1、使用fullkey进行删改查时的where子句形式如下： WHERE key1=x1 AND key2=x2 AND key3=x3; 2、使用fullkey+过滤条件进行删改查时的where子句形式如下，若过滤条件中包含OR运算符，则必须对过滤条件加括号： WHERE key1=x1 AND key2=x2 AND key3=x3 AND (过滤条件); 3、使用partkey进行删改查时的where子句形式如下： WHERE key1=x1 AND key2=x2; 4、使用partkey+过滤条件进行删改查时的where子句形式如下，若过滤条件中包含OR运算符，则必须对过滤条件加括号： WHERE key1=x1 AND key2=x2 AND (过滤条件); 当where子句中的必选部分为partkey时，where子句的执行结果可能是多条记录。

删除操作

1、通过fullkey删除单条记录时，SQL语句有以下两种形式：

DELETE FROM demo WHERE key1=x1 AND key2=x2 AND key3=x3;
DELETE FROM demo WHERE key1=x1 AND key2=x2 AND key3=x3 AND (过滤条件);

2、通过fullkey批量删除记录时，SQL语句形式如下： DELETE FROM demo WHERE key1=x1 AND key2=x2 AND key3=x3; DELETE FROM demo WHERE key1=x4 AND key2=x5 AND key3=x6; 删除/批量删除操作不支持partkey，批量删除操作暂不支持过滤条件。

更新操作

1、通过fullkey更新单条记录时，SQL语句有以下两种形式：

UPDATE demo SET value1=x1, value2=x2 WHERE key1=x1 AND key2=x2 AND key3=x3;
UPDATE demo SET value1=x1, value2=x2 WHERE key1=x1 AND key2=x2 AND key3=x3 AND (过滤条件);

2、通过fullkey批量更新记录时，SQL语句形式如下： UPDATE demo SET value1=x1, value2=x2 WHERE key1=x3 AND key2=x4 AND key3=x5; UPDATE demo SET value1=x6, value2=x7 WHERE key1=x8 AND key2=x9 AND key3=x10; 更新/批量更新操作不支持partkey，批量更新操作暂不支持过滤条件。

查询操作

1、通过fullkey查询单条记录时，SQL语句有以下四种形式：

SELECT * FROM demo WHERE key1=x1 AND key2=x2 AND key3=x3;
SELECT * FROM demo WHERE key1=x1 AND key2=x2 AND key3=x3 AND (过滤条件);
SELECT key1,value1 FROM demo WHERE key1=x1 AND key2=x2 AND key3=x3;
SELECT key1,value1 FROM demo WHERE key1=x1 AND key2=x2 AND key3=x3 AND (过滤条件);

2、通过partkey查询多条记录时，SQL语句有以下四种形式：

SELECT * FROM demo WHERE key1=x1 AND key2=x2;
SELECT * FROM demo WHERE key1=x1 AND key2=x2 AND (过滤条件);
SELECT key1,value1 FROM demo WHERE key1=x1 AND key2=x2;
SELECT key1,value1 FROM demo WHERE key1=x1 AND key2=x2 AND (过滤条件);

3、通过fullkey批量查询记录时，SQL语句的形式如下： SELECT * FROM demo WHERE key1=x1 AND key2=x2 AND key3=x3 OR key1=x4 AND key2=x5 AND key3=x6; 批量查询操作暂不支持过滤条件。 4、通过partkey批量查询记录时，SQL语句的形式如下： SELECT * FROM demo WHERE key1=x1 AND key2=x2 OR key1=x3 AND key2=x4; 批量查询操作暂不支持过滤条件。

全局索引查询

TcaplusDB提供sql查询语句进行索引查询，其中，sql查询条件中的字段必须是建立了全局索引的字段，另外，如果是聚合查询，那么聚合查询的字段也必须是建立了全局索引的字段； 一个索引查询请求，当前限制最多返回3000条记录；

支持的sql查询语句

条件查询

支持 =, >, >=, <, <=, !=, between, in, not in, like, not like, and, or , 比如:

SELECT * FROM `mail` WHERE user_id>="10004" AND server_id=100;
SELECT * FROM `mail` WHERE user_id BETWEEN 10000 AND 10003 AND server_id=100;
SELECT * FROM `mail` WHERE user_id="10000" AND server_id=100 AND mail_id LIKE "210507%";
SELECT * FROM `mail` WHERE user_id>="10004" OR server_id<=200;

注意：between查询时，between a and b，对应的查询范围为[a, b]，比如 between 1 and 100, 是会包含1和100这两个值的，即查询范围为[1,100] 注意：like查询是支持模糊匹配，其中"%"通配符，匹配0个或者多个字符； “_”通配符，匹配1个字符；

分页查询

支持limit offset分页查询，比如： SELECT * FROM mail WHERE user_id>"10000" LIMIT 100 OFFSET 2; 注意：当前limit必须与offset搭配使用，即不支持limit 1 或者 limit 0,1这种；

聚合查询

当前支持的聚合查询包括：sum, count, max, min, avg，比如： SELECT server_id, COUNT(DISTINCT user_id), COUNT(*), SUM(state) FROM \mail` WHERE user_id>="10000" AND server_id=100;` 注意：聚合查询不支持limit offset，即limit offset 不生效； 注意：目前只有count支持distinct，即 select count(distinct(a)) from table where a > 1000; 其他情况均不支持distinct

部分字段查询

支持查询部分字段的值，比如： SELECT user_id, \subject` FROM mail WHERE user_id>="10000";` ### 不支持的sql查询语句

不支持聚合查询与非聚合查询混用

select , a, b from table where a > 1000; select sum(a), a, b from table where a > 1000; select count(), * from table where a > 1000;

不支持order by查询

select * from table where a > 1000 order by a;

不支持group by查询

select * from table where a > 1000 group by a;

不支持having查询

select sum(a) from table where a > 1000 group by a having sum(a) > 10000;

不支持多表联合查询

select * from table1 where table1.a > 1000 and table1.a = table2.b;

不支持嵌套select查询

select * from table where a > 1000 and b in (select b from table where b < 5000);

不支持的其他查询

（1）不支持join查询； （2）不支持union查询； （3）不支持类似 select a+b from table where a > 1000 的查询； （4）不支持类似 select from table where a+b > 1000 的查询； （5） 不支持类似 select from table where a >= b 的查询； （6）不支持其他未提到的查询；

事务支持

TcaplusDB暂不支持跨数据行的事务。 调用TcaplusDB SQL Driver/C++的Connection.commit()方法，实际上是将多条增删改语句（从上次commit到当前时间通过Statement.executeUpdate()方法执行的语句）一并提交给服务端执行。这里需要注意的是，由于多条语句是在同一个请求中发送到服务端，受请求包大小的限制，这里当前限制每次提交的语句上限是100条。 由于暂不支持跨数据行的事务，同一批提交的语句，有可能部分成功，部分失败，此时可以先通过Statement.getUpdateCount()方法，获取实际增删改的数据条，判断是否符合预期，与些同时，也可以通过Statement.getResultSet()获取增删改失败的数据主键信息，后台会通过该接口将失败的数据的主键列的值返回给应用。

特定平台考虑因素

Windows

在Windows上，可以在不同的构建配置中构建应用程序，这些配置确定最终可执行文件使用的C++运行时库的类型：

• 应用程序可以在32位或64位模式下构建.

• 可以在发布或调试模式下构建应用程序。

• 您可以在动态运行时库( /MD 链接器选项)或静态运行库( /MT 链接器选项)。MSVC编译器的不同版本也使用运行时库的不同版本。

要构建TcaplusDB SQL Driver/C++应用程序，使用Windows的构建人员必须满足以下条件：

• 需要MicrosoftVisualStudio的可接受版本。

• 应用程序应该使用与构建TcaplusDB SQL Driver/C++相同的构建配置。生成配置包括构建模式(发布模式或调试模式)和链接器选项(例如， /MD 或 /MDd ).

• 运行客户端应用程序的目标主机必须具有可接受版本的Visual C++。

以下部分提供了有关构建TcaplusDB SQL Driver/C++应用程序的几个方面的其他详细信息：

应用程序构建配置必须与TcaplusDB SQL Driver/C++匹配

使用兼容的编译器版本构建应用程序和TcaplusDB SQL Driver/C++非常重要。使用与构建TcaplusDB SQL Driver/C++相同的构建配置构建应用程序也很重要。也就是说，应用程序应该使用相同的构建模式和链接器选项，以确保TcaplusDB SQL Driver/C++和应用程序使用相同的运行时库。 下表显示了适用于构建模式和运行时库的每个组合的链接器选项。它还显示了每个组合是否可以从TcaplusDB获得TcaplusDB SQL Driver/C++二进制包。(如果不是，您必须自己构建TcaplusDB SQL Driver/C++。) 表5.1每个构建模式和运行时库的TcaplusDB SQL Driver/C++链接器选项

表5.2目前支持的版本信息对应关系

发布包在windows下的使用

• tsf4gbase库，下载对应版本，请注意VC的版本，采用MD（多线程DLL）或MT（多线程静态），还有Debug或Release版本

• 添加tsf4gbase库目录：工程---属性---配置属性---VC++目录---库目录：加上lib文件存放目录.

• 解压TcaplusDB SQL Driver/C++发布包，vs2015(及以上版本)新建工程.

• 添加工程的头文件目录：工程---属性---配置属性---c/c++---常规---附加包含目录：加上头文件存放目录.

• 添加文件引用的lib静态库路径：工程---属性---配置属性---链接器---常规---附加库目录：加上lib文件存放目录.

• 然后添加工程引用的lib文件名：工程---属性---配置属性---链接器---输入---附加依赖项：加上lib文件名

当前支持接口

Connection

/*
Creates a Statement object for sending SQL statements to the database. SQL statements without parameters are normally executed using Statement objects. 
If the same SQL statement is executed many times, it may be more efficient to use a PreparedStatement object.
Returns:
    a new default Statement object
Throws:
    SQLException - if a database access error occurs or this method is called on a closed connection
*/
sql::Statement * createStatement();
/*
Retrieves the driver that produced this connection object.
Returns:
    the driver that produced this connection object
Throws:
    SQLException - if a database access error occurs
*/
Driver *getDriver();
/*
Releases this Connection object's database 
Specified by:
    close in interface AutoCloseable
Throws:
    SQLException - SQLException if a database access error occurs
*/
void close();
/*
Retrieves a DatabaseMetaData object that contains metadata about the database to which this Connection object represents a connection. 
The metadata includes information about the database's tables, its supported SQL grammar, its stored procedures, the capabilities of this connection, and so on.
Returns:
    a DatabaseMetaData object for this Connection object
Throws:
    SQLException - if a database access error occurs or this method is called on a closed connection
*/
sql::DatabaseMetaData * getMetaData();
/*
Retrieves whether this Connection object has been closed. A connection is closed if the method close has been called on it or if certain fatal errors have occurred. 
This method is guaranteed to return true only when it is called after the method Connection.close has been called.
This method generally cannot be called to determine whether a connection to a database is valid or invalid. 
A typical client can determine that a connection is invalid by catching any exceptions that might be thrown when an operation is attempted.
Returns:
    true if this Connection object is closed; false if it is still open
Throws:
    SQLException - if a database access error occurs
*/
bool isClosed();
/*
Creates a PreparedStatement object for sending parameterized SQL statements to the database.
A SQL statement with or without IN parameters can be pre-compiled and stored in a PreparedStatement object. 
This object can then be used to efficiently execute this statement multiple times.
Parameters:
    sql - an SQL statement that may contain one or more '?' IN parameter placeholders
Returns:
    a new default PreparedStatement object containing the pre-compiled SQL statement
Throws:
    SQLException - if a database access error occurs or this method is called on a closed connection
*/
sql::PreparedStatement * prepareStatement(const sql::SQLString& sql);

DatabaseMetaData

/*
Retrieves a description of the tables available in the connection. 
Each table description has the following columns:
TABLE_CAT String => table catalog (may be null)
TABLE_SCHEM String => table schema (may be null)
TABLE_NAME String => table name
TABLE_TYPE String => table type. Typical types are "TABLE", "VIEW", "SYSTEM TABLE", "GLOBAL TEMPORARY", "LOCAL TEMPORARY", "ALIAS", "SYNONYM".
REMARKS String => explanatory comment on the table
TYPE_CAT String => the types catalog (may be null)
TYPE_SCHEM String => the types schema (may be null)
TYPE_NAME String => type name (may be null)
SELF_REFERENCING_COL_NAME String => name of the designated "identifier" column of a typed table (may be null)
REF_GENERATION String => specifies how values in SELF_REFERENCING_COL_NAME are created. Values are "SYSTEM", "USER", "DERIVED". (may be null)
Note: Some databases may not return information for all tables.
Parameters:
catalog - a catalog name; must match the catalog name as it is stored in the database; (not support)
schemaPattern - a schema name pattern; must match the schema name as it is stored in the database; (not support)
tableNamePattern - a table name pattern; must match the table name as it is stored in the database; (not support)
types - a list of table types, which must be from the list of table types returned from getTableTypes(),to include; (not support)
Returns:
    ResultSet - each row is a table description
Throws:
    SQLException - if a database access error occurs
*/
sql::ResultSet * getTables(const sql::SQLString& catalog, const sql::SQLString& schemaPattern, const sql::SQLString& tableNamePattern, std::list<sql::SQLString> &types);
/*
Retrieves a description of table columns available in the connection.
Each column description has the following columns:
TABLE_CAT String => table catalog (may be null)
TABLE_SCHEM String => table schema (may be null)
TABLE_NAME String => table name
COLUMN_NAME String => column name
DATA_TYPE int => SQL type from java.sql.Types
TYPE_NAME String => Data source dependent type name, for a UDT the type name is fully qualified
COLUMN_SIZE int => column size.
BUFFER_LENGTH is not used.
DECIMAL_DIGITS int => the number of fractional digits. Null is returned for data types where DECIMAL_DIGITS is not applicable.
NUM_PREC_RADIX int => Radix (typically either 10 or 2)
NULLABLE int => is NULL allowed.
columnNoNulls - might not allow NULL values
columnNullable - definitely allows NULL values
columnNullableUnknown - nullability unknown
REMARKS String => comment describing column (may be null)
COLUMN_DEF String => default value for the column, which should be interpreted as a string when the value is enclosed in single quotes (may be null)
SQL_DATA_TYPE int => unused
SQL_DATETIME_SUB int => unused
CHAR_OCTET_LENGTH int => for char types the maximum number of bytes in the column
ORDINAL_POSITION int => index of column in table (starting at 1)
IS_NULLABLE String => ISO rules are used to determine the nullability for a column.
YES --- if the column can include NULLs
NO --- if the column cannot include NULLs
empty string --- if the nullability for the column is unknown
SCOPE_CATALOG String => catalog of table that is the scope of a reference attribute (null if DATA_TYPE isn't REF)
SCOPE_SCHEMA String => schema of table that is the scope of a reference attribute (null if the DATA_TYPE isn't REF)
SCOPE_TABLE String => table name that this the scope of a reference attribute (null if the DATA_TYPE isn't REF)
SOURCE_DATA_TYPE short => source type of a distinct type or user-generated Ref type, SQL type from java.sql.Types (null if DATA_TYPE isn't DISTINCT or user-generated REF)
IS_AUTOINCREMENT String => Indicates whether this column is auto incremented
YES --- if the column is auto incremented
NO --- if the column is not auto incremented
empty string --- if it cannot be determined whether the column is auto incremented
IS_GENERATEDCOLUMN String => Indicates whether this is a generated column
YES --- if this a generated column
NO --- if this not a generated column
empty string --- if it cannot be determined whether this is a generated column
The COLUMN_SIZE column specifies the column size for the given column. For numeric data, this is the maximum precision. For character data, this is the length in characters. For datetime datatypes, this is the length in characters of the String representation (assuming the maximum allowed precision of the fractional seconds component). For binary data, this is the length in bytes. For the ROWID datatype, this is the length in bytes. Null is returned for data types where the column size is not applicable.
Parameters:
catalog - a catalog name; must match the catalog name as it is stored in the database; (not support)
schemaPattern - a schema name pattern; must match the schema name as it is stored in the database; (not support)
tableNamePattern - a table name pattern; must match the table name as it is stored in the database
columnNamePattern - a column name pattern; must match the column name as it is stored in the database (not support)
Returns:
ResultSet - each row is a column description
Throws:
SQLException - if a database access error occurs
*/
sql::ResultSet * getColumns(const sql::SQLString& catalog, const sql::SQLString& schemaPattern, const sql::SQLString& tableNamePattern, const sql::SQLString& columnNamePattern);
/*
Retrieves the connection that produced this metadata object.
Returns:
    the connection that produced this metadata object
Throws:
    SQLException - if a database access error occurs
*/
sql::Connection * getConnection();

Statement

/*
Retrieves the connection that produced this statement object.
Returns:
    the connection that produced this statement object
Throws:
    SQLException - if a database access error occurs
*/
sql::Connection * getConnection();
/*
Releases this Statement object
Specified by:
    close in interface AutoCloseable
Throws:
    SQLException - if a database access error occurs
*/
void close();
/*
Executes the given SQL statement, which may return multiple results. In some (uncommon) situations, a single SQL statement may return multiple result sets and/or update counts. 
Normally you can ignore this unless you are (1) executing a stored procedure that you know may return multiple results or (2) you are dynamically executing an unknown SQL string.
The execute method executes an SQL statement and indicates the form of the first result. You must then use the methods getResultSet or getUpdateCount to retrieve the result, 
and getMoreResults to move to any subsequent result(s).
Note:This method cannot be called on a PreparedStatement or CallableStatement.
Parameters:
    sql - any SQL statement
Returns:
    true if the first result is a ResultSet object; false if it is an update count or there are no results
Throws:
    SQLException - if a database access error occurs, this method is called on a closed Statement, the method is called on a PreparedStatement or CallableStatement
    SQLTimeoutException - when the driver has determined that the timeout value that was specified by the setQueryTimeout method has been exceeded and has at least 
    attempted to cancel the currently running Statement
*/
bool execute(const sql::SQLString& sql);
/*
Executes the given SQL statement, which returns a single ResultSet object.
Note:This method cannot be called on a PreparedStatement or CallableStatement.
Parameters:
    sql - an SQL statement to be sent to the database, typically a static SQL SELECT statement
Returns:
    a ResultSet object that contains the data produced by the given query; never null
Throws:
    SQLException - if a database access error occurs, this method is called on a closed Statement, the given SQL statement produces anything other than a single ResultSet object, 
    the method is called on a PreparedStatement or CallableStatement
    SQLTimeoutException - when the driver has determined that the timeout value that was specified by the setQueryTimeout method has been exceeded and has at least 
    attempted to cancel the currently running Statement
*/
sql::ResultSet * executeQuery(const sql::SQLString& sql);
/*
Executes the given SQL statement, which may be an INSERT, UPDATE, or DELETE statement or an SQL statement that returns nothing, such as an SQL DDL statement.
Note:This method cannot be called on a PreparedStatement or CallableStatement.
Parameters:
    sql - an SQL Data Manipulation Language (DML) statement, such as INSERT, UPDATE or DELETE; or an SQL statement that returns nothing, such as a DDL statement.
Returns:
    either (1) the row count for SQL Data Manipulation Language (DML) statements or (2) 0 for SQL statements that return nothing
Throws:
    SQLException - if a database access error occurs, this method is called on a closed Statement, the given SQL statement produces a ResultSet object, 
    the method is called on a PreparedStatement or CallableStatement
    SQLTimeoutException - when the driver has determined that the timeout value that was specified by the setQueryTimeout method has been exceeded and has at least 
    attempted to cancel the currently running Statement
*/
int executeUpdate(const sql::SQLString& sql);
/*
Retrieves the current result as a ResultSet object. This method should be called only once per result.
Returns:
    the current result as a ResultSet object or null if the result is an update count or there are no more results
Throws:
    SQLException - if a database access error occurs or this method is called on a closed Statement
*/
sql::ResultSet * getResultSet();
/*
Retrieves the current result as an update count; if the result is a ResultSet object or there are no more results, -1 is returned. This method should be called only once per result.
Returns:
    the current result as an update count; -1 if the current result is a ResultSet object or there are no more results
Throws:
    SQLException - if a database access error occurs or this method is called on a closed Statement
*/
uint64_t getUpdateCount();
/*
Retrieves the number of seconds the driver will wait for a Statement object to execute.(default 5 second) If the limit is exceeded, a SQLException is thrown.
Returns:
    the current query timeout limit in seconds; zero means there is no limit
Throws:
    SQLException - if a database access error occurs or this method is called on a closed Statement
*/
unsigned int getQueryTimeout();
/*
Sets the number of seconds the driver will wait for a Statement object to execute to the given number of seconds. By default there is 5 second
Parameters:
    seconds - the new query timeout limit in seconds; zero means there is no limit
Throws:
    SQLException - if a database access error occurs, this method is called on a closed Statement or the condition seconds >= 0 is not satisfied
*/
void setQueryTimeout(unsigned int seconds);

PreparedStatement

/*
Retrieves the connection that produced this prepared statement object.
Returns:
    the connection that produced this prepared statement object
Throws:
    SQLException - if a database access error occurs
*/
sql::Connection *getConnection();
/*
Clears the current parameter values immediately.
In general, parameter values remain in force for repeated use of a statement. Setting a parameter value automatically clears its previous value. 
However, in some cases it is useful to immediately release the resources used by the current parameter values; this can be done by calling the method clearParameters.
Throws:
    SQLException - if a database access error occurs or this method is called on a closed PreparedStatement
*/
void clearParameters();
/*
Releases this Prepared Statement object
Specified by:
    close in interface AutoCloseable
Throws:
    SQLException - SQLException if a database access error occurs
*/
void close();
/*
Executes the SQL statement in this PreparedStatement object, which may be any kind of SQL statement. Some prepared statements return multiple results; 
the execute method handles these complex statements as well as the simpler form of statements handled by the methods executeQuery and executeUpdate.
The execute method returns a boolean to indicate the form of the first result. You must call either the method getResultSet or getUpdateCount to retrieve the result; 
you must call getMoreResults to move to any subsequent result(s).
Returns:
    true if the first result is a ResultSet object; false if the first result is an update count or there is no result
Throws:
    SQLException - if a database access error occurs; this method is called on a closed PreparedStatement or an argument is supplied to this method
    SQLTimeoutException - when the driver has determined that the timeout value that was specified by the setQueryTimeout method has been exceeded and has at least 
    attempted to cancel the currently running Statement
*/
bool execute();
/*
Executes the SQL statement in this PreparedStatement object, which may be any kind of SQL statement. Some prepared statements return multiple results; 
the execute method handles these complex statements as well as the simpler form of statements handled by the methods executeQuery and executeUpdate.
The execute method returns a boolean to indicate the form of the first result. You must call either the method getResultSet or getUpdateCount to retrieve the result; 
you must call getMoreResults to move to any subsequent result(s).
Parameters:
    sql - an SQL statement that may contain one or more '?' IN parameter placeholders
Returns:
    true if the first result is a ResultSet object; false if the first result is an update count or there is no result
Throws:
    SQLException - if a database access error occurs; this method is called on a closed PreparedStatement or an argument is supplied to this method
    SQLTimeoutException - when the driver has determined that the timeout value that was specified by the setQueryTimeout method has been exceeded and has at least 
    attempted to cancel the currently running Statement
*/
bool execute(const sql::SQLString& sql);
/*
Executes the SQL query in this PreparedStatement object and returns the ResultSet object generated by the query.
Returns:
a ResultSet object that contains the data produced by the query; never null
Throws:
    SQLException - if a database access error occurs; this method is called on a closed PreparedStatement or the SQL statement does not return a ResultSet object
    SQLTimeoutException - when the driver has determined that the timeout value that was specified by the setQueryTimeout method has been exceeded and has at least 
    attempted to cancel the currently running Statement
*/
sql::ResultSet *executeQuery();
/*
Executes the SQL query in this PreparedStatement object and returns the ResultSet object generated by the query.
Parameters:
    sql - an SQL statement that may contain one or more '?' IN parameter placeholders
Returns:
a ResultSet object that contains the data produced by the query; never null
Throws:
    SQLException - if a database access error occurs; this method is called on a closed PreparedStatement or the SQL statement does not return a ResultSet object
    SQLTimeoutException - when the driver has determined that the timeout value that was specified by the setQueryTimeout method has been exceeded and has at least 
    attempted to cancel the currently running Statement
*/
sql::ResultSet *executeQuery(const sql::SQLString& sql);
/*
Executes the SQL statement in this PreparedStatement object, which must be an SQL Data Manipulation Language (DML) statement, such as INSERT, UPDATE or DELETE; 
or an SQL statement that returns nothing, such as a DDL statement.
Returns:
    either (1) the row count for SQL Data Manipulation Language (DML) statements or (2) 0 for SQL statements that return nothing
Throws:
    SQLException - if a database access error occurs; this method is called on a closed PreparedStatement or the SQL statement returns a ResultSet object
    SQLTimeoutException - when the driver has determined that the timeout value that was specified by the setQueryTimeout method has been exceeded and has at least 
    attempted to cancel the currently running Statement
*/
int executeUpdate();
/*
Executes the SQL statement in this PreparedStatement object, which must be an SQL Data Manipulation Language (DML) statement, such as INSERT, UPDATE or DELETE; 
or an SQL statement that returns nothing, such as a DDL statement.
Parameters:
    sql - an SQL statement that may contain one or more '?' IN parameter placeholders
Returns:
    either (1) the row count for SQL Data Manipulation Language (DML) statements or (2) 0 for SQL statements that return nothing
Throws:
    SQLException - if a database access error occurs; this method is called on a closed PreparedStatement or the SQL statement returns a ResultSet object
    SQLTimeoutException - when the driver has determined that the timeout value that was specified by the setQueryTimeout method has been exceeded and has at least 
    attempted to cancel the currently running Statement
*/
int executeUpdate(const sql::SQLString& sql);
/*
Sets the number of seconds the driver will wait for a Statement object to execute to the given number of seconds. By default there is 5 second
Parameters:
    seconds - the new query timeout limit in seconds; zero means there is no limit
Throws:
    SQLException - if a database access error occurs, this method is called on a closed Statement or the condition seconds >= 0 is not satisfied
*/
void setQueryTimeout(unsigned int seconds);
/*
Retrieves the number of seconds the driver will wait for a Statement object to execute.(default 5 second) If the limit is exceeded, a SQLException is thrown.
Returns:
    the current query timeout limit in seconds; zero means there is no limit
Throws:
    SQLException - if a database access error occurs or this method is called on a closed Statement
*/
unsigned int getQueryTimeout();
/*
Retrieves the current result as a ResultSet object. This method should be called only once per result.
Returns:
    the current result as a ResultSet object or null if the result is an update count or there are no more results
Throws:
    SQLException - if a database access error occurs or this method is called on a closed Statement
*/
sql::ResultSet * getResultSet();
/*
Retrieves the current result as an update count; if the result is a ResultSet object or there are no more results, -1 is returned. This method should be called only once per result.
Returns:
    the current result as an update count; -1 if the current result is a ResultSet object or there are no more results
Throws:
    SQLException - if a database access error occurs or this method is called on a closed Statement
*/
uint64_t getUpdateCount();
/*
Sets the designated parameter to a istream object. The driver converts this to an SQL VARBINARY value when it sends it to the database.
Parameters:
    parameterIndex - index of the first parameter is 1, the second is 2, ...
    inputStream - An object that contains the data to set the parameter value to.
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setBlob(unsigned int parameterIndex, std::istream * inputStream);
/*
Sets the designated parameter to the given data time value. e.g '2016:08:02 12:12:30' The driver converts this to an SQL BIGINT value when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    value - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setDateTime(unsigned int parameterIndex, const sql::SQLString& value);
/*
Sets the designated parameter to the given double value. The driver converts this to an SQL DOUBLE value when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    value - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setDouble(unsigned int parameterIndex, double value);
/*
Sets the designated parameter to the given int32_t value. The driver converts this to an SQL INTEGER value when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    value - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setInt(unsigned int parameterIndex, int32_t value);
/*
Sets the designated parameter to the given uint32_t value. The driver converts this to an SQL INTEGER value when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    value - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setUInt(unsigned int parameterIndex, uint32_t value);
/*
Sets the designated parameter to the given int64_t value. The driver converts this to an SQL BIGINT value when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    value - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setInt64(unsigned int parameterIndex, int64_t value);
/*
Sets the designated parameter to the given uint64_t value. The driver converts this to an SQL BIGINT value when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    value - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setUInt64(unsigned int parameterIndex, uint64_t value);
/*
Sets the designated parameter to the given String value. The driver converts this to an SQL VARCHAR when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    x - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setString(unsigned int parameterIndex, const sql::SQLString& value);
/*
Sets the designated parameter to the given int8_t value. The driver converts this to an SQL TINYINT when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    x - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setInt8(unsigned int parameterIndex, int8_t value);
/*
Sets the designated parameter to the given uint8_t value. The driver converts this to an SQL TINYINT when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    x - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setUInt8(unsigned int parameterIndex, uint8_t value);
/*
Sets the designated parameter to the given int16_t value. The driver converts this to an SQL SMALLINT when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    x - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setInt16(unsigned int parameterIndex, int16_t value);
/*
Sets the designated parameter to the given uint16_t value. The driver converts this to an SQL SMALLINT when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    x - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setUInt16(unsigned int parameterIndex, uint16_t value);
/*
Sets the designated parameter to the given float value. The driver converts this to an SQL REAL value when it sends it to the database.
Parameters:
    parameterIndex - the first parameter is 1, the second is 2, ...
    value - the parameter value
Throws:
    SQLException - if parameterIndex does not correspond to a parameter marker in the SQL statement; 
    if a database access error occurs or this method is called on a closed PreparedStatement
*/
void setFloat(unsigned int parameterIndex, float value);

ResultSet

/*
Releases this ResultSet object
When a ResultSet is closed, any ResultSetMetaData instances that were created by calling the getMetaData method remain accessible.
Calling the method close on a ResultSet object that is already closed is a no-op.
Specified by:
    close in interface AutoCloseable
Throws:
    SQLException - if a database access error occurs
*/
void close();
/*
Maps the given ResultSet column label to its ResultSet column index.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column index of the given column name
Throws:
    SQLException - if the ResultSet object does not contain a column labeled columnLabel, a database access error occurs or this method is called on a closed result set
*/
uint32_t findColumn(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a Blob istream.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    a Blob object representing the SQL BLOB value in the specified column
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
*/
std::istream * getBlob(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a Blob istream.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    a Blob object representing the SQL BLOB value in the specified column
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
*/
std::istream * getBlob(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a bool type.
If the designated column has a datatype of CHAR or VARCHAR and contains a "0" or has a datatype of BIT, TINYINT, SMALLINT, INTEGER or BIGINT and contains a 0, 
a value of false is returned. If the designated column has a datatype of CHAR or VARCHAR and contains a "1" or has a datatype of BIT, TINYINT, SMALLINT, INTEGER or 
BIGINT and contains a 1, a value of true is returned.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is false
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
bool getBoolean(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a bool type.
If the designated column has a datatype of CHAR or VARCHAR and contains a "0" or has a datatype of BIT, TINYINT, SMALLINT, INTEGER or BIGINT and contains a 0, 
a value of false is returned. If the designated column has a datatype of CHAR or VARCHAR and contains a "1" or has a datatype of BIT, TINYINT, SMALLINT, INTEGER or 
BIGINT and contains a 1, a value of true is returned.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is false
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
bool getBoolean(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a double type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
long double getDouble(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a double type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
long double getDouble(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an int32_t type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
int32_t getInt(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an int32_t type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
int32_t getInt(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an uint32_t type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
uint32_t getUInt(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an uint32_t type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
uint32_t getUInt(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an int64_t type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
int64_t getInt64(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an int64_t type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
int64_t getInt64(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an uint64_t type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
uint64_t getUInt64(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an uint64_t type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
uint64_t getUInt64(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an int8_t type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
int8_t getInt8(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an int8_t type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
int8_t getInt8(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an uint8_t type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
uint8_t getUInt8(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an uint8_t type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
uint8_t getUInt8(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an int16_t type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
int16_t getInt16(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an int16_t type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
int16_t getInt16(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an uint16_t type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
uint16_t getUInt16(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an uint16_t type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
uint16_t getUInt16(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an float type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
float getFloat(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as an float type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
float getFloat(const sql::SQLString& columnLabel) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a String type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is ""
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
SQLString getString(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a String type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is ""
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
SQLString getString(const sql::SQLString& columnLabel) const;
/*
Retrieves the number, types and properties of this ResultSet object's columns.
Returns:
    the description of this ResultSet object's columns
Throws:
    SQLException - if a database access error occurs or this method is called on a closed result set
*/
sql::ResultSetMetaData * getMetaData() const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a time_t type.
Parameters:
    columnIndex - the first column is 1, the second is 2, ...
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
*/
time_t getTimestamp(uint32_t columnIndex) const;
/*
Retrieves the value of the designated column in the current row of this ResultSet object as a time_t type.
Parameters:
    columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
    the column value; if the value is SQL NULL, the value returned is 0
Throws:
    SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
*/
time_t getTimestamp(const sql::SQLString& columnLabel) const;
/*
Moves the cursor froward one row from its current position. A ResultSet cursor is initially positioned before the first row; the first call to the method next makes 
the first row the current row; the second call makes the second row the current row, and so on.
When a call to the next method returns false, the cursor is positioned after the last row. Any invocation of a ResultSet method which requires a current row will result 
in a SQLException being thrown. If the result set type is TYPE_FORWARD_ONLY, it is vendor specified whether their JDBC driver implementation will return false or 
throw an SQLException on a subsequent call to next.
Returns:
    true if the new current row is valid; false if there are no more rows
Throws:
    SQLException - if a database access error occurs or this method is called on a closed result set
*/
bool next();
/*
Retrieves whether this ResultSet object has been closed. A ResultSet is closed if the method close has been called on it, or if it is automatically closed.
Returns:
    true if this ResultSet object is closed; false if it is still open
Throws:
    SQLException - if a database access error occurs
*/
bool isClosed() const;

ResultSetMetaData

/*
Returns the number of columns in this ResultSet object.
Returns:
    the number of columns
Throws:
    SQLException - if a database access error occurs
*/
unsigned int getColumnCount();
/*
Gets the designated column's suggested title for use in printouts and displays. The suggested title is usually specified by the SQL AS clause. 
If a SQL AS is not specified, the value returned from getColumnLabel will be the same as the value returned by the getColumnName method.
Parameters:
    column - the first column is 1, the second is 2, ...
Returns:
    the suggested column title
Throws:
    SQLException - if a database access error occurs
*/
SQLString getColumnLabel(unsigned int columnIndex);
/*
Get the designated column's name.
Parameters:
    column - the first column is 1, the second is 2, ...
Returns:
    column name
Throws:
    SQLException - if a database access error occurs
*/
SQLString getColumnName(unsigned int columnIndex);
/*
Retrieves the designated column's SQL type.
Parameters:
    column - the first column is 1, the second is 2, ...
Returns:
    SQL type from java.sql.Types
Throws:
    SQLException - if a database access error occurs
*/
int getColumnType(unsigned int columnIndex);
/*
Retrieves the designated column's database-specific type name.
Parameters:
    column - the first column is 1, the second is 2, ...
Returns:
    type name used by the database. If the column type is a user-defined type, then a fully-qualified type name is returned.
Throws:
    SQLException - if a database access error occurs
*/
SQLString getColumnTypeName(unsigned int columnIndex);

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