Transform MySQL table and rows - php

Question

I have one problem here, and I don't even have clue what to Google and how to solve this.
I am making PHP application to export and import data from one MySQL table into another. And I have problem with these tables.
In source table it looks like this:
And my destination table has ID, and pr0, pr1, pr2 as rows. So it looks like this:
Now the problem is the following: If I just copy ( insert every value of 1st table as new row in second) It will have like 20.000 rows, instead of 1000 for example.
Even if I copy every record as new row in second database, is there any way I can fuse rows ? Basically I need to check if value exists in last row with that ID_, if it exist in that row and column (pr2 for example) then insert new row with it, but if last row with same ID_ does not have value in pr2 column, just update that row with value in pr2 column.
I need idea how to do it in PHP or MySQL.

Answer 1

So you got a few Problems:
1) copy the table from SQL to PHP, pay attention to memory usage, run your script with the PHP command Memory_usage(). it will show you that importing SQL Data can be expensive. Look this up. another thing is that PHP DOESNT realese memory on setting new values to array. it will be usefull later on.
2)i didnt understand if the values are unique at the source or should be unique at the destination table.. So i will assume that all the source need to be on the destination as is.
I will also assume that pr = pr0 and quant=pr1.
3) you have missmatch names.. that can also be an issue. would take care of that..also.
4) will use My_sql, as the SQL connector..and $db is connected..
SCRIPT:
<?PHP
$select_sql = "SELECT * FROM Table_source";
$data_source = array();
while($array_data= mysql_fetch_array($select_sql)) {
$data_source[] = $array_data;
$insert_data=array();
}
$bulk =2000;
foreach($data_source as $data){
if(isset($start_query) == false)
{
$start_query = 'REPLACE INTO DEST_TABLE ('ID_','pr0','pr1','pr2')';
}
$insert_data[]=implode(',',$data).',0)';// will set 0 to the
if(count($insert_data) >=$bulk){
$values = implode('),(',$insert_data);
$values = substr(1,2,$values);
$values = ' VALUES '.$values;
$insert_query = $start_query.' '.$values;
$mysqli->query($insert_query);
$insert_data = array();
} //CHECK THE SYNTAX IM NOT SURE OF ALL OF IT MOSTLY THE SQL PART>> SEE THAT THE QUERY IS OK
}
if(count($insert_data) >=$bulk) // IF THERE ARE ANY EXTRA PIECES..
{
$values = implode('),(',$insert_data);
$values = substr(1,2,$values);
$values = ' VALUES '.$values;
$insert_query = $start_query.' '.$values;
$mysqli->query($insert_query);
$insert_data = null;
}
?>
ITs off the top off my head but check this idea and tell me if this work, the bugs night be in small things i forgot with the QUERY structure, print this and PASTE to PHPmyADMIN or you DB query and see its all good, but this concept will sqve a lot of problems..