Deal with big data high concurrency related issues

Handle Big Data high concurrency problems
Inside the database
Database
A
Table has 1 sheets
A
The data inside is
FirstName LastName
A A
This table contains millions data.
So that's the problem.
/* The front $name is already defined by me */
$result = "SELECT LastName from a WHERE firstname= '". $name. "'";
$sql _name=mysql_query ($result);
$name =mysql_fetch_array ($sql _title);
$subject = $name [0];
?>
So that's the problem.
Server one processing at the same time 500 concurrent databases are hung up.
Is there any good way to solve it?




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Unfortunately, this is your hardware and the operating system does not support you that high concurrency.
Only from the perspective of PHP can not change the status quo
For your code:
There's no room for optimization at the PHP level.
At the MySQL level, it's just indexing the FirstName column.

------to solve the idea----------------------
$result = "SELECT LastName from a WHERE firstname= '". $name. "'";
And
$result = "SELECT LastName from a WHERE firstname= '". $name. "' Limit 0,1 ';
The meaning is different!

The former indicates that multiple lines may be removed
The latter means that no matter how many lines are taken, only the first row encountered

If, for the so-called speed, even the original intention is distorted. What's the point of "optimization"?
------to solve the idea----------------------
By a horizontal or vertical table, or by means of a multi-database divider.

------to solve the idea----------------------
I mean the sub-list of the library ...
MD5 (FIRSTNAME+LASTNAME), hashed into a different database table.

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