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mysql_insert_id() or LAST_INSERT_ID()

amitbravo asked
Medium Priority
Last Modified: 2013-12-12
I need to do like > 
$sql=mysql_query("INSERT INTO blog (id, subject) VALUES (NULL,'mytext')");
just after this I need to insert another information in another table where I need to set same Unique ID of last query like :

$sql2=mysql_query("INSERT INTO blog2 (id, subject) VALUES (mysql_insert_id(),'second text')");

Though this all works fine but I am wondering what if 1000 users are visiting the site same time and inserting rows so could it be incorrect because of it . what after executing first line from a users PC and before second line  if some other user execute the  same the code ?
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Billing Engineer
Most Valuable Expert 2014
Top Expert 2009
that code will work fine, as you use the same connection/session.

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UmeshSenior Principal Technical Support Engineer
Top Expert 2009

Use LAST_INSERT_ID() instead of mysql_insert_id()

so your query should be

$sql2=mysql_query("INSERT INTO blog2 (id, subject) VALUES ( LAST_INSERT_ID(),'second text')");
UmeshSenior Principal Technical Support Engineer
Top Expert 2009

sorry I misread the question.. both works LAST_INSERT_ID() & mysql_insert_id().. and there would not be any problem no matter 1000 user or 1000K user ..



then I am going to use mysql_insert_id() .
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