PHP连接SQLite数据库

PHP连接SQLite数据库

SQLite3扩展名在PHP 5.3.0+以上都会默认启用。可以在编译时使用--without-sqlite3来禁用它。

Windows用户可通过启用php_sqlite3.dll才能使用此扩展。 php_sqlite3.dll默认包含在PHP 5.3.0之后的PHP发行版中。

有关详细的安装说明,请查看PHP教程及其官方网站。

连接到SQLite数据库

以下PHP代码显示如何连接到SQLite数据库。 如果数据库不存在,那么它将创建一个新的数据库,最后将返回一个数据库对象。

<?php
   class SQLiteDB extends SQLite3
   {
      function __construct()
      {
         $this->open('phpdb.db');
      }
   }
   $db = new SQLiteDB();
   if(!$db){
      echo $db->lastErrorMsg();
   } else {
      echo "Yes, Opened database successfully\n";
   }
?>

现在,运行上面的程序在当前目录中创建指定数据库:phpdb.db。可以根据需要更改路径。 如果数据库成功创建,则会提供以下消息:

在执行上面语句后,应该也会在相同的目录下自动创建一个名称为:phpdb.db的数据库文件。如下所示 -

创建表

以下PHP程序将用于在上面创建的数据库(phpdb.db)中创建一个表:

<?php
class SQLiteDB extends SQLite3
{
  function __construct()
  {
     $this->open('phpdb.db');
  }
}
$db = new SQLiteDB();
if(!$db){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Opened database successfully<br/>\n";
}

$sql =<<<EOF
      CREATE TABLE company
      (ID INT PRIMARY KEY     NOT NULL,
      NAME           TEXT    NOT NULL,
      AGE            INT     NOT NULL,
      ADDRESS        CHAR(50),
      SALARY         REAL);
EOF;

$ret = $db->exec($sql);
if(!$ret){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Table created successfully<br/>\n";
}
$db->close();

当执行上述程序时,它将在数据库(phpdb.db)中创建一个名称为:company的表,并显示以下消息:

插入数据操作

以下PHP程序显示了如何在上述示例中创建的company表中插入数据记录:

<?php
class SQLiteDB extends SQLite3
{
  function __construct()
  {
     $this->open('phpdb.db');
  }
}
$db = new SQLiteDB();
if(!$db){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Opened database successfully<br/>\n";
}

// 先删除后创建表
$sql = "DROP table company";
$ret = $db->exec($sql);

// 创建表语句

$sql =<<<EOF
      CREATE TABLE if not exists company
      (ID INT PRIMARY KEY     NOT NULL,
      NAME           TEXT    NOT NULL,
      AGE            INT     NOT NULL,
      ADDRESS        CHAR(50),
      SALARY         REAL);
EOF;

$ret = $db->exec($sql);
if(!$ret){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Table created successfully<br/>\n";
}

// $db->close();

$sql =<<<EOF
      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (1, 'Maxsu', 26, 'Haikou', 20000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (2, 'Allen', 25, 'Guangzhou', 15000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (3, 'Tenny', 23, 'Shanghai', 20000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (4, 'Weiwang', 25, 'Beijing ', 65000.00 );
EOF;

   $ret = $db->exec($sql);
   if(!$ret){
      echo $db->lastErrorMsg();
   } else {
      echo "Yes, Some Records has Inserted successfully<br/>\n";
   }
   $db->close();

当执行上述程序时,将向company表中插入给定的记录,并显示如下:

SELECT操作

以下PHP程序显示了如何从上述示例中创建的company表中获取并显示数据记录:

<?php
class SQLiteDB extends SQLite3
{
  function __construct()
  {
     $this->open('phpdb.db');
  }
}
$db = new SQLiteDB();
if(!$db){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Opened database successfully<br/>\n";
}

// 先删除后创建表
$sql = "DROP table company";
$ret = $db->exec($sql);

// 创建表

$sql =<<<EOF
      CREATE TABLE if not exists company
      (ID INT PRIMARY KEY     NOT NULL,
      NAME           TEXT    NOT NULL,
      AGE            INT     NOT NULL,
      ADDRESS        CHAR(50),
      SALARY         REAL);
EOF;

$ret = $db->exec($sql);
if(!$ret){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Table created successfully<br/>\n";
}

// $db->close();

$sql =<<<EOF
      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (1, 'Maxsu', 26, 'Haikou', 20000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (2, 'Allen', 25, 'Guangzhou', 15000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (3, 'Tenny', 23, 'Shanghai', 20000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (4, 'Weiwang', 25, 'Beijing ', 65000.00 );
EOF;

$ret = $db->exec($sql);
if(!$ret){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Some Records has Inserted successfully<br/>\n";
}

// 查询表中的数据

echo "<b> Select Data from company table :</b><hr/>";

$sql =<<<EOF
  SELECT * from COMPANY;
EOF;

$ret = $db->query($sql);
while($row = $ret->fetchArray(SQLITE3_ASSOC) ){
  echo "ID = ". $row['ID'] . "<br/>\n";
  echo "NAME = ". $row['NAME'] ."<br/>\n";
  echo "ADDRESS = ". $row['ADDRESS'] ."<br/>\n";
  echo "SALARY =  ".$row['SALARY'] ."<br/>\n\n";
  echo '----------------------------------<br/>';
}

echo "Operation done successfully\n";

$db->close();

执行上述程序时,会产生以下结果:

更新操作

以下PHP代码显示了如何使用UPDATE语句来更新记录,然后从company表中获取并显示更新的记录:

<?php
class SQLiteDB extends SQLite3
{
  function __construct()
  {
     $this->open('phpdb.db');
  }
}
$db = new SQLiteDB();
if(!$db){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Opened database successfully<br/>\n";
}

// 先删除后创建表
$sql = "DROP table company";
$ret = $db->exec($sql);

// 创建表

$sql =<<<EOF
      CREATE TABLE if not exists company
      (ID INT PRIMARY KEY     NOT NULL,
      NAME           TEXT    NOT NULL,
      AGE            INT     NOT NULL,
      ADDRESS        CHAR(50),
      SALARY         REAL);
EOF;

$ret = $db->exec($sql);
if(!$ret){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Table created successfully<br/>\n";
}

// $db->close();

$sql =<<<EOF
      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (1, 'Maxsu', 26, 'Haikou', 20000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (2, 'Allen', 25, 'Guangzhou', 15000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (3, 'Tenny', 23, 'Shanghai', 20000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (4, 'Weiwang', 25, 'Beijing ', 65000.00 );
EOF;

$ret = $db->exec($sql);
if(!$ret){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Some Records has Inserted successfully<br/>\n";
}

// 更新ID=1的薪水为:29999

$sql = 'UPDATE COMPANY set SALARY = 29999.00 where ID=1';
$ret = $db->exec($sql);
if(!$ret){
  echo $db->lastErrorMsg();
} else {
  echo $db->changes(), " Record(ID=1) updated successfully<br/>\n";
}


// 查询表中的数据

echo "<b> Select Data from company table :</b><hr/>";

$sql =<<<EOF
  SELECT * from COMPANY;
EOF;

$ret = $db->query($sql);
while($row = $ret->fetchArray(SQLITE3_ASSOC) ){
  echo "ID = ". $row['ID'] . "<br/>\n";
  echo "NAME = ". $row['NAME'] ."<br/>\n";
  echo "ADDRESS = ". $row['ADDRESS'] ."<br/>\n";
  echo "SALARY =  ".$row['SALARY'] ."<br/>\n\n";
  echo '----------------------------------<br/>';
}

echo "Operation done successfully\n";

$db->close();

执行上述程序时,会产生以下结果:

删除操作

以下PHP代码显示了如何使用DELETE语句删除任何记录,然后从company表中获取并显示剩余的记录:

<?php
class SQLiteDB extends SQLite3
{
  function __construct()
  {
     $this->open('phpdb.db');
  }
}
$db = new SQLiteDB();
if(!$db){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Opened database successfully<br/>\n";
}

// 先删除后创建表
$sql = "DROP table company";
$ret = $db->exec($sql);

// 创建表

$sql =<<<EOF
      CREATE TABLE if not exists company
      (ID INT PRIMARY KEY     NOT NULL,
      NAME           TEXT    NOT NULL,
      AGE            INT     NOT NULL,
      ADDRESS        CHAR(50),
      SALARY         REAL);
EOF;

$ret = $db->exec($sql);
if(!$ret){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Table created successfully<br/>\n";
}

// $db->close();

$sql =<<<EOF
      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (1, 'Maxsu', 26, 'Haikou', 20000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (2, 'Allen', 25, 'Guangzhou', 15000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (3, 'Tenny', 23, 'Shanghai', 20000.00 );

      INSERT INTO company (ID,NAME,AGE,ADDRESS,SALARY)
      VALUES (4, 'Weiwang', 25, 'Beijing ', 65000.00 );
EOF;

$ret = $db->exec($sql);
if(!$ret){
  echo $db->lastErrorMsg();
} else {
  echo "Yes, Some Records has Inserted successfully<br/>\n";
}

// 更新ID小于等于2的数据记录

$sql =<<<EOF
  DELETE from COMPANY where ID<=2;
EOF;
$ret = $db->exec($sql);
if(!$ret){
 echo $db->lastErrorMsg();
} else {
  echo $db->changes(), " Record(ID<=2) deleted successfully<br/>\n";
}

// 查询表中的数据

echo "<b> Select Data from company table :</b><hr/>";

$sql =<<<EOF
  SELECT * from COMPANY;
EOF;

$ret = $db->query($sql);
while($row = $ret->fetchArray(SQLITE3_ASSOC) ){
  echo "ID = ". $row['ID'] . "<br/>\n";
  echo "NAME = ". $row['NAME'] ."<br/>\n";
  echo "ADDRESS = ". $row['ADDRESS'] ."<br/>\n";
  echo "SALARY =  ".$row['SALARY'] ."<br/>\n\n";
  echo '----------------------------------<br/>';
}

echo "Operation done successfully\n";

$db->close();

执行上述程序时,会产生以下结果:

由于其它操作都类似,只需写上对应SQL语句,然后使用PHP执行即可,所以其它的示例在这里就不再一一演示了。如有疑问,可以留言联系。


目录

SQLite主键