Mysqli fetch_assoc vs fetch_array

fetch_array returns value with indexing. But Fetch_assoc just returns the the value.

for example fetch_array returns

[0] => 11
[id] => 11
[1] => 2014-12-29
[date] => 2014-12-29

here array location 0 contains 11 also this location name is 'id'.

same things fetch_assoc will returns

[id] => 11
[date] => 2014-12-29

means just returns the value.

fetch_array will give you key/value pairs and with indexes, where as fetch_assoc will give you only the key/value pairs but not with indexes. For example:

//fetch_array output be like:
[name]=>'someName'
[0]=>'someName'
[email]=>'[email protected]'
[1]=>'[email protected]'

//fetch_assoc output be like

[name]=>'someName'
[email]=>'[email protected]'

It's all about performance

fetch_array() returns one array with both numeric keys, and associative strings (column names), so here you can either use $row['column_name'] or $row[0]

Where as fetch_assoc() will return string indexed key array and no numeric array so you won't have an option here of using numeric keys like $row[0].

So the latter one is better in performance compared to fetch_array() and obviously using named indexes is far better compared to numeric indexes.

(PHP 5) From: http://php.net/manual/en/mysqli-result.fetch-array.php

mysqli_result::fetch_array -- mysqli_fetch_array — Fetch a result row as an associative, a numeric array, or both

So effectively, fetch_array() and fetch_assoc() can be essentially equivalent calls. As for performance, I recommend using whichever call that results in more readable code and only be concerned about the performance after you've clearly identified the call as a performance issue. It's more likely that you've got more serious performance issues where you least expect them to be.