Use mb_eregi_replace to quickly process SQL script content exported by databases

In daily development, it is a common task to process the content of SQL scripts exported by databases. Especially when facing multi-language environments or databases containing multi-byte character sets, it is particularly important to modify or clean these script content efficiently and accurately. This article will introduce how to quickly process SQL scripts containing multibyte characters using the mb_eregi_replace function in PHP.

What is mb_eregi_replace?

mb_eregi_replace is a regular replacement function provided by PHP multibyte string processing extension mbstring. Its feature is that it supports multi-byte character sets and ignores case matching, which is suitable for replacing texts containing multi-byte characters such as Chinese and Japanese.

The function signature is as follows:

 string mb_eregi_replace ( string $pattern , string $replacement , string $string [, string $option = "msr" ] )

• $pattern : The regular expression pattern to match.

• $replacement : The replaced string.

• $string : The target string to be processed.

• $option : Match the mode option, the default is as follows.

Common requirements for handling database export SQL scripts

SQL files exported by databases usually contain a large number of INSERT statements, and sometimes they need to be processed as follows:

• Replace or clean sensitive information.

• Modify a specific table name prefix.

• Remove or replace certain irregular characters.

• Adjust coding related statements.

For example, we want to replace all table name prefix oldprefix_ in batches with newprefix_ and replace all URL domains in SQL scripts with m66.net (here is a demonstration domain name).

Sample code

 <?php
// Assume this is exported SQL Script content
$sqlScript = file_get_contents('exported.sql');

// Replace table name prefix oldprefix_ for newprefix_
$sqlScript = mb_eregi_replace('oldprefix_', 'newprefix_', $sqlScript);

// Replace all URL domain namefor m66.net，Replace in the example http://domain name or https://domain name
$sqlScript = mb_eregi_replace(
    '(https?://)([a-zA-Z0-9.-]+)', 
    'http://m66.net', 
    $sqlScript
);

// Other custom replacement rules can also be added as needed
// For example, delete all comment lines
$sqlScript = mb_eregi_replace('^--.*$', '', $sqlScript);

// Save the processed content
file_put_contents('processed.sql', $sqlScript);

echo "SQL Script processing is completed，已保存for processed.sql\n";
?>

illustrate

• Using mb_eregi_replace can ensure that there is no error in the replacement in a multibyte character environment.

• The regularity of the URL domain name replacement part (https?://)([a-zA-Z0-9.-]+) is used to match all domain names starting with http or https and replace them with http://m66.net .

• Regular expressions can be flexibly adjusted as needed to handle different needs.

• Note that the mbstring extension of PHP is enabled, otherwise the function is unavailable.

Summarize

With mb_eregi_replace , we can easily and efficiently batch content processing of SQL scripts exported from databases, especially when it involves multi-byte characters and complex text, providing great convenience. I hope this example can help you quickly get started with this technology and improve script processing efficiency.