mysql使用什么函数来执行mysql语句 定义和用法 mysql_query() 函数执行一条 MySQL 查询。 语法 mysql_query(query,connection)参数 描述 query 必需。规定要发送的 SQL 查询。注释:查询字符串不应以分号结束。 connection 可
mysql使用什么函数来执行mysql语句
定义和用法
mysql_query() 函数执行一条 MySQL 查询。
语法
mysql_query(query,connection)参数 描述
query 必需。规定要发送的 SQL 查询。注释:查询字符串不应以分号结束。
connection 可选。规定 SQL 连接标识符。如果未规定,则使用上一个打开的连接。
说明
如果没有打开的连接,本函数会尝试无参数调用 mysql_connect() 函数来建立一个连接并使用之。
返回值
mysql_query() 仅对 SELECT,SHOW,,EXPLAIN 或 DESCRIBE 语句返回一个资源标识符,如果查询执行不正确则返回 FALSE。
对于其它类型的 SQL 语句,mysql_query() 在执行成功时返回 TRUE,出错时返回 FALSE。
非 FALSE 的返回值意味着查询是合法的并能够被服务器执行。这并不说明任何有关影响到的或返回的行数。很有可能一条查询执行成功了但并未影响到或并未返回任何行。
提示和注释
注释:该函数自动对记录集进行读取和缓存。如需运行非缓存查询,请使用 mysql_unbuffered_query()。
例子 1
$con = mysql_connect("localhost","mysql_user","mysql_pwd");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
$sql = "SELECT * FROM Person";
mysql_query($sql,$con);
// 一些代码
mysql_close($con);
?>
例子 2
通过 mysql_query() 函数创建一个新数据库:
$con = mysql_connect("localhost","mysql_user","mysql_pwd");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
$sql = "CREATE DATABASE my_db";
if (mysql_query($sql,$con))
{
echo "Database my_db created";
}
else
{
echo "Error creating database: " . mysql_error();
}
?>

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