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Use LAST_INSERT_ID() instead of mysql_insert_id()<br />
<br />
so your query should be<br />
<br />
$sql2=mysql_query(&quot;INSERT INTO blog2 (id, subject) VALUES ( LAST_INSERT_ID(),'second text')&quot;);
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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')");

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sorry I misread the question.. both works LAST_INSERT_ID() &amp;&nbsp;mysql_insert_id().. and there would not be any problem no matter 1000 user or 1000K user ..<br />
<br />
<a href="http://dev.mysql.com/doc/refman/5.0/en/getting-unique-id.html" rel="ugc nofollow">http://dev.mysql.com/doc/refman/5.0/en/getting-unique-id.html</a>
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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 ..

http://dev.mysql.com/doc/refman/5.0/en/getting-unique-id.html [http://dev.mysql.com/doc/refman/5.0/en/getting-unique-id.html]

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then I am going to use mysql_insert_id() .
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then I am going to use mysql_insert_id() .

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I need to do like &gt;&nbsp;<br />
$sql=mysql_query(&quot;INSERT INTO blog (id, subject) VALUES (NULL,'mytext')&quot;);<br />
just after this I need to insert another information in another table where I need to set same Unique ID of last query like :<br />
<br />
$sql2=mysql_query(&quot;INSERT INTO blog2 (id, subject) VALUES (mysql_insert_id(),'second<wbr /> text')&quot;);<br />
<br />
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 &nbsp;if some other user execute the &nbsp;same the code ? 
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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 ? 

mysql_insert_id() or LAST_INSERT_ID()

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