What is the usage of php limit?

php limit usage: 1. Limit the number of results, the code is [$User = M('User');]; 2. Paging query, the code is [$Article = M('Article');$ Article->limit('10,25')->select();].

##php limit usage:

Usage 1. Limit the number of results

For example, to obtain 10 users who meet the requirements, call the following:

$User = M('User');
 $User->where('status=1')->field('id,name')->limit(10)->select();

The limit method can also be used for write operations, such as updating 3 pieces of data that meet the requirements:

$User = M('User');
$User->where('score=100')->limit(3)->save(array('level'=>'A'));

Usage 2. Paging query

is used for paging query of articles where the limit method is more commonly used, for example:

$Article = M('Article');
$Article->limit('10,25')->select();

means querying article data, 25 pieces of data starting from row 10 (it may also depend on the influence of where conditions and limit sorting, not to mention this for now).

After version 3.1, you can also use it like this:

$Article = M('Article');
$Article->limit(10,25)->select();

For large data tables, try to use limit to limit query results, otherwise it will cause huge memory overhead and performance problems.

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