php postgresql错误，准备好的语句已经存在

Question

Am getting an error of prepared statement "my_query7" already exists, i call this function each time a user tries to update table leader_info in the database, i have gone through the documentation for pg_prepare and i don't understand what is meant by it should only be run once. code snippets will be of help. Thanks.

 function add_leader_country($user_id,$l_country)
 {
   global $connection;
   $query = pg_prepare($connection,"my_query7","update leader_info set l_country = $1 where user_id = $2 and status < 9"); 
$result = pg_execute($connection,"my_query7",array($l_country,$user_id));
if(!$result)
{
  echo pg_last_error($connection);
} 
else 
{
  echo "Records created successfully
";
}
$row = pg_affected_rows($result);
return $row;



 }

Answer 1

Prepare execute does not permit duplicate naming, so that is your error. A query should only be prepared once, for example, in a cycle for the preparation state must be set out of the for and its execution in the for.

 $result=$pg_prepare($connection,"my_query7",$query);
    for($id=1;$id<3;$id++){
      $result=pg_execute($connection,"my_query7",array($l_country,$user_id));
       ...
    }

In your case using a functio that use the prepare and execute multiple times it's a problem.

What are you trying to accomplish with this function dispatches more code like where you are calling the function. This way I might be able to help you.

If you want to use functions I would use this method

Exemple from https://secure.php.net

<?php
function requestToDB($connection,$request){
    if(!$result=pg_query($connection,$request)){
        return False;
    }
    $combined=array();
    while ($row = pg_fetch_assoc($result)) {
        $combined[]=$row;
    }
    return $combined;
}
?>

<?php
$conn = pg_pconnect("dbname=mydatabase");

$results=requestToDB($connect,"select * from mytable");

//You can now access a "cell" of your table like this:
$rownumber=0;
$columname="mycolumn";

$mycell=$results[$rownumber][$columname];
var_dump($mycell); 

If you whant to use preaper and execute functions try to create a function that creates the preparations only once in a session. Do not forget to give different names so that the same error does not occur. I tried to find something of the genre and did not find. If you find a form presented here for others to learn. If in the meantime I find a way I present it.