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1. freelancer_loken
   Member
   Posted 3 years ago #

   Hi,

   It's been a week since I have been struggling with this problem. I have a plugin that should create its own custom database tables.
   Here is a snippet of my code
   

   global $wpdb;
   
   function create_load_table(){
   $table_name = $wpdb->prefix.'name';
   
   if($wpdb->get_var("SHOW TABLES LIKE '$table_name'") != $table_name){
   $create_name_table_query = "CREATE TABLE ".$table_name."(
   Name_Key int(8) NOT NULL AUTO_INCREMENT,
   Firstname char(25) NOT NULL,
   Middlename char(25) NOT NULL,
   Lastname char(25) NOT NULL,
   Birthday date NOT NULL,
   PRIMARY KEY  ('Name_Key')
   );";
   
   require_once(ABSPATH . 'wp-admin/upgrade-functions.php');
   dbDelta($create_name_table_query);
   }
   
   register_activation_hook(__FILE__,'create_name_table');

   It get's activated whenever I click the activate option, but when I check the database, no tables are created. I am testing this one on localhost before I deploy to our actual webserver.

   Can anyone tell me what I am doing wrong. I have tried a lot of things, and it's been driving me nuts..

   Any help would gladly be appreciated.

   Thanks in anticipation,

   Loken

2. MichaelH
   Volunteer
   Posted 3 years ago #

   Shouldn't this:
   

   register_activation_hook(__FILE__,'create_name_table');

   be
   

   register_activation_hook(__FILE__,'create_load_table');

3. freelancer_loken
   Member
   Posted 3 years ago #

   My bad

   I think I had a typo error
   Ok, I have changed it to the function to be called at activation but it still does not create any table

4. riledhel
   Member
   Posted 3 years ago #

   Change your code to this one and try again:

   function create_load_table(){
   global $wpdb;
   $table_name = $wpdb->prefix.'name';
   
   if($wpdb->get_var("SHOW TABLES LIKE '$table_name'") != $table_name){
   $create_name_table_query = "CREATE TABLE ".$table_name."(
   Name_Key int(8) NOT NULL AUTO_INCREMENT,
   Firstname char(25) NOT NULL,
   Middlename char(25) NOT NULL,
   Lastname char(25) NOT NULL,
   Birthday date NOT NULL,
   PRIMARY KEY  ('Name_Key')
   );";
   
   require_once(ABSPATH . 'wp-admin/upgrade-functions.php');
   dbDelta($create_name_table_query);
   }
   
   register_activation_hook(__FILE__,'create_load_table');

   I think it's a scope problem. Your defining $wpdb outside the scope of the function where you're using it, so PHP just creates an empty variable $wpdb in the function's scope. Hope it helps.

5. freelancer_loken
   Member
   Posted 3 years ago #

   ok, i will try that. so would that mean that if i intend to use the variable sometime within another function scope, it's assumed that it's contains the previously stored value as declared outside the function scope?

6. riledhel
   Member
   Posted 3 years ago #

   Let's clarify:

   global $example;
   
   function a(){
       echo $example; //prints nothing. $example isn't in the same scope, so a variable $example is created with '' as it's value.
   }
   
   function b(){
       global $example;
       echo $example; //prints the value of $example.
       $example = 'Hello World';
   }
   
   function c(){
       global $example;
       echo $example; //prints 'Hello World' because the $example value was changed in the b function and it's a global variable.
   }
   
   a();
   b();
   c();

7. freelancer_loken
   Member
   Posted 3 years ago #

   Ok, thanks a lot for clarifying that one for me.
   It's a lot of help...

   Thanks,

   Loken

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