php pdo sql如果存在行则返回

Question

In PHP PDO trying to use SELECT COUNT(*) SQL to see if primary key exists (so then can update rather than insert),

When I call the function sqlCall; fetchColumn() returns 0 or 1 depending on if it exists or not, however when it is returned it always returns false?

How do I get it to return if row exists or not?

Thanks for help!!

 function sqlCall($primary) {

            $sql = $handler->prepare("SELECT COUNT(*) FROM  WHERE ". strtolower($primary)."=:".$primary);

            $sSqlParams = array(':'.$primary => $primary);

            $sql->execute($sSqlParams);


            if($sql->fetchColumn()==1){
                return 1;

            } else {
                return 0;
            }
            break;
}




try {
                $rows = sqlCall($primary);

                if($rows=True){
                    //UPDATE SQL
                } else {
                    //INSERT SQL
                }
}
catch(PDOException $er) {

                    die();
}

Answer 1

You are going about this wrong way - there is MySQL construct which allows you to do this without any need for workarounds. If you would like to update record if exists and if not insert it than use: INSERT ... ON DUPLICATE KEY UPDATE

It goes like this:

INSERT INTO table (primary_key, field_to_update) VALUES(primary_key_value, value_to_update) ON DUPLICATE KEY UPDATE field_to_update = value_to_update

Whenever your primar_key will be already in database the record will be updated and if primary_key does not exists than new record will be created.