From PDO to SQLSRV | 易学教程

问题

I used PDO for MYSql before but now i need to use Microsoft SQL Server Driver for PHP.

I found the manual. http://php.net/manual/en/book.sqlsrv.php

I use Example #2 to connect to the new SQL database: http://www.php.net/manual/en/function.sqlsrv-connect.php

How do I 'convert' the following (PDO mysql) to work with sqlsrv:

$username = 'test';

try {
$conn = new PDO('mysql:host=$host;dbname=$database', $username, password);
$stmt = $conn->prepare('SELECT username users WHERE username = :username LIMIT 1');
$stmt->execute(array('username' => $username));

if ($stmt->rowCount() > 0) {
$result = $stmt->fetch();

    echo $result['username'];

} else {
    echo 'Nothing found.';
die();
}
} catch(PDOException $e) {
echo 'ERROR: ' . $e->getMessage();
}

回答1:

After solving the connections issues, you have to convert the SQL statement written using MySQL SQL dialect to T-SQL dialectal (used by SQL Server).

[1] SQL Server doesn't has the LIMIT clause. More, this clause is not included in SQL standard. Instead, you can use ROW_NUMBER() function. But, in this case, you don't have to use this function because ...

[2] ... the username column from users table should accept only unique values (and, off course, it should be mandatory). So, you have to be sure that you have an unique constraint or an unique index on username column. This script will check if you have an unique index on username column:

DECLARE @TableName SYSNAME=N'dbo.users';
DECLARE @ColumnName SYSNAME=N'username';
SELECT  *
FROM    sys.indexes i
WHERE   i.object_id=OBJECT_ID(@TableName)
AND     i.is_unique=1
AND     EXISTS (
    SELECT  *
    FROM    sys.index_columns ic 
    INNER JOIN sys.columns c ON c.object_id=ic.object_id
    AND     c.column_id=ic.column_id
    WHERE   i.object_id=ic.object_id
    AND     i.index_id=ic.index_id
    AND     ic.is_included_column=0
    AND     c.name=@ColumnName
)
AND (
    SELECT  COUNT(*)
    FROM    sys.index_columns ic 
    INNER JOIN sys.columns c ON c.object_id=ic.object_id
    AND     c.column_id=ic.column_id
    WHERE   i.object_id=ic.object_id
    AND     i.index_id=ic.index_id
    AND     ic.is_included_column=0
)=1;

[3] If you have an unique index on username column then you don't need to use the LIMIT 1 clause (or ROW_NUMBER() function) because the SQL statement will return always zero(min.) or one(max.) record(s).

[4] The SQL statement should be SELECT username FROM users WHERE username = :param.

回答2:

From php.net

PHP Data Objects (PDO) extension defines a lightweight, consistent interface for accessing databases in PHP.

Since you already use PDO for MySQL, you may consider use the PDO driver for MS SQL like dev-null-dweller said. SQLSRV driver is another choice to access MS SQL. But it will require a overhaul of your current PHP code.

Microsoft provide two kinds of PHP drivers for MS SQL:

php_sqlsrv.dll provides a unique set of SQLSRV API specified for MS SQL.

php_pdo_sqlsrv.dll provides a set of mostly PDO compatible API for MS SQL.

Note your PHP version when downloading the driver:

Version 4.0 supports PHP 7.0+ on Windows and Linux
Version 3.2 supports PHP 5.6, 5.5, and 5.4 on Windows
Version 3.1 supports PHP 5.5 and 5.4 on Windows
Version 3.0 supports PHP 5.4 on Windows

And for PHP5.6 Microsoft provide only driver for x86 version. Unofficial X64 driver can find on http://robsphp.blogspot.tw/2012/06/unofficial-microsoft-sql-server-driver.html

After you download the driver. Copy the version you need to your PHP ext folder. And add the driver name into php.ini configurations, for example:

extension=php_pdo_sqlsrv_56_ts.dll

Then restart the web server. You can confirm the PDO driver is install correctly if there is a section pdo_sqlsrv display by the phpinfo() function.

And please note, MS use an different DSN in the PDO constructor. The line

$conn = new PDO('mysql:host=$host;dbname=$database', $username, password);

Should be changed to

$conn = new PDO('sqlsrv:Server=$host;Database=$database', $username, password);

Then you should not meet the "ERROR: could not find driver" again. Hope this help.

来源：https://stackoverflow.com/questions/13109012/from-pdo-to-sqlsrv

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php

sql-server

database

sqlsrv