how to concatenate sql queries - php

Question

i am trying to concatenate sql queries and run later after loop. how is that possible? this is my vision:
for($i=1;$i<=10;$i++){
$item_.$i = "value_".$i;
sql = sql . " insert into table (`item`) values ('$item_'.$i.'')";
// this should be but an array
}
and save into db:
for($j=0;$j<sqlarray.length;$j++){
$sql_done = mysql_query($sqlarray[$j]);
}
i didnot try anything yet, because the database is big and i am afraid of destroying something important with my code..
thanks a lot

Answer 1

Use mysqli and bindings
see http://www.php.net/manual/en/mysqli.prepare.php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
// define your query
$query = "INSERT INTO tablename (column1,column2) VALUES (:col1,:col2)";
if ($stmt = $mysqli->prepare($query)) {
// loop of insert
for($i=0;$i<10;$i++){
$stmt->bind_param("col1", $i);
$stmt->bind_param("col2", 'test'.$i);
$stmt->execute();
}
$stmt->close();
}else{
throw new Exception("unable to prepare query");
}
$mysqli->close();
Binding will avoid a lot of security issue, no one should use something else then binding ever.
Even better put everything in a transaction and in case of error your database remains unchanged.
see: http://www.php.net/manual/en/mysqli.commit.php for more info
and here is a proposal with commit or rollback
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
if (mysqli_connect_errno()) {
throw new Exception("Unable to connect");
}else{
try{
$mysqli->autocommit(FALSE);
// define your query
$query = "INSERT INTO tablename (column1,column2) VALUES (:col1,:col2)";
if ($stmt = $mysqli->prepare($query)) {
// loop of insert
for($i=0;$i<10;$i++){
$stmt->bind_param("col1", $i);
$stmt->bind_param("col2", 'test'.$i);
$stmt->execute();
}
$stmt->close();
}else{
throw new Exception("unable to prepare query");
}
$mysqli->commit();
}catch(Exception $e){
$mysqli->rollback();
}
$mysqli->close();
}
I did not try it but we should be near a good (best practice?) solution.
I hope this could help you.

Answer 2

For insert query you can write code like below:
$sql .= " insert into table (`item`) values ";
for($i=1;$i<=10;$i++){
$item_.$i = "value_".$i;
$sql = $sql . " ('$item_'.$i.''),";
}
mysqli_query( substr($sql ,0,-1) );
The above will concatenate all the insert data in a single string and execute at once.

Answer 3

I hope you were looking for this
$query = "insert into table_name values";
for($i=0;$i<4;$i++) {
$data1 = "test_".$i;
$data2 = "new_".$i;
$query .= "('','$data1','$data2'),";
}
$query = substr($query,0,-1);
echo $query;
Let me know

Answer 4

try below code
$sql="":
for($i=1;$i<=10;$i++)
{
$item_.$i = "value_".$i;
$sql.=" insert into table (`item`) values ('$item_'.$i.'')";
// this should be but an array
}
mysql_query($sql);