April 2026
Intermediate
1009 pages
34h 15m
English
Content preview from PHP and MySQL
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8.5 Search and Sort
This section summarizes functions that filter elements out of an array or put the elements of the array in a different order in some way.
8.5.1 Search
There are some interesting functions for searching. We present the most important ones here:
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The array_key_exists(Index, Array) function determines whether an index is present in the array and returns a truth value as the result.
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array_search(Value, Array, Exactly) searches the array for a value and returns the key or keys. If there are several, it returns an array. If the optional Exactly option is set to true, then the data type is also included in the search. Caution: as with in_array(), the search term is placed before the array itself!
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array_keys(Array, Value, ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.