In_array large array query performance problems

: This article mainly introduces the query performance of the in_array Large Array. if you are interested in the PHP Tutorial, please refer to it. Problem

Recently, when implementing a project interface, we found that when the array is too large, the data returns slowly. The maximum response time returned by the interface data is 2 s. after repeated debugging, it is found that the most time-consuming part of the code segment isin_array()Function.

Solution process

In stackoverflow, I found an article that provides my solutions.
-Which is faster, array_key_exists or array_search?

The article says:

array_key_existsIs much faster.array_searchMust traverse the whole array, so it is O (n ).array_key_existsIs a hash table lookup, so it is O (1 ).

---- Split line ----

I think it's faster for PHP to check for keys (array_key_exists()Or simplyisset($array[$key])). To search for a value, PHP must cycle through the array; to search for a key PHP will use a hash function.

This array is used to save the user account and is not destroyed and stored in the memory.

Original array
$array=array('account1','account2','$account3');

Modified array
$array=array('account1'=>0,'account2'=>0,'$account3'=>0)

Useisset($array[$account]))To check whether the account exists in this array.

Summary

Becausein_array()The function traverses and queries the array. O (n) increases as n (array length) increases. Thereforein_array()Efficiency should be considered for functions.

When dealing with large array queries, we should try to use key queries instead of value queries in PHP.

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The above describes the in_array large array query performance issues, including the content, hope to be helpful to friends interested in PHP tutorials.