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$oldArr = [ ['a', 1], ['', 2], ['', 3], ['b', 4], ['', 5], ['c',6], ['',7] ]; 转换为 $newArr = [ 'a'=>'1,2,3', 'b'=>'4,5', 'c'=>'6,7' ]
Shouldn’t we think about why the arrays are spliced like this?
I feel that when fetching it from the database, it can be processed with mysql built-in functionssuch as concat() or concat_group()
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
Shouldn’t we think about why the arrays are spliced like this?
I feel that when fetching it from the database, it can be processed with mysql built-in functions
such as concat() or concat_group()