Home Database Mysql Tutorial mysql教程删除数据sql语句用法

mysql教程删除数据sql语句用法

Jun 07, 2016 pm 04:20 PM
mysql delete Tutorial data usage statement

mysql教程删除数据sql语句用法 DELETE FROM 语句用于从数据库表中删除记录。 语法 DELETE FROM table_name WHERE column_name = some_value 注释:SQL 对大小写不敏感。DELETE FROM 与 delete from 等效。 为了让 PHP 执行上面的语句,我们必须使用 mysql_qu

   mysql教程删除数据sql语句用法

  DELETE FROM 语句用于从数据库表中删除记录。

  语法

  DELETE FROM table_name WHERE column_name = some_value

  注释:SQL 对大小写不敏感。DELETE FROM 与 delete from 等效。

  为了让 PHP 执行上面的语句,我们必须使用 mysql_query( 函数。该函数用于向 SQL 连接发送查询和命令。

  例子

  稍早时,,我们在本教程中创建了一个名为 "Person" 的表。它看起来类似这样:

  FirstName LastName Age

  Peter Griffin 35

  Glenn Quagmire 33

  下面的例子删除 "Person" 表中所有 LastName='Griffin' 的记录:

  $con = mysql_connect("localhost","peter","abc123");

  if (!$con)

  {

  die('Could not connect: ' . mysql_error());

  }

  mysql_select_db("my_db", $con);

  mysql_query("DELETE FROM Person WHERE LastName='Griffin'");

  mysql_close($con);

  ?>

  在这次删除之后,表是这样的:

  FirstName LastName Age

  Peter Griffin 35

        :更多精彩文章请关注三联编程教程栏目。

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