Mysql Update, 2 databases - mysql

Question

I have 2 MYSQL tables and when I pick up dates from table A which contains only 1 column and lets say 10 rows with dates
$result = mysql_query("SELECT * FROM A");
$row = mysql_fetch_assoc($result);
And after I want to UPDATE another table B with using this dates from table A mysql_query("UPDATE B SET something='1' WHERE name='".$row['name']."'")
So i need to update the second table, but its updating just once with first date from table A, and other 9 its ignoring. So my question is, how to make updating of second table with each date from 1 table?

Answer 1

You need to run a the updates in a loop. After executing your query
$result = mysql_query("SELECT * FROM A");
and verifying that it has succeeded (make sure $result is not null), instead of fetching one row, use a loop:
while($row = mysql_fetch_assoc($result)){
// perform calculations & assignments with the $row elements
$result2 = mysql_query("UPDATE B SET something='1'
WHERE name='".$row['name']."'");
if(! $result2){
echo "update failed";
}
// Any other stuff you need to do
}
Alternatively:
If the something in the update is the same for all the rows, you can change your first query to give you a coma-separated string of names:
$result = mysql_query("SELECT CONCAT("'",GROUP_CONCAT(name SEPARATOR "','"),"'")
AS all_names FROM A");
This way, you receive only one row, and you can then use it in your second query:
$result2 = mysql_query("UPDATE B SET something='1'
WHERE name IN (".$row['name'].")");