using more than 1 database

[leeming]

i am trying to write a function, so that i can switch been which database i am using, but i am having some problem with it.  ???

[code]function CDB($id)
{
    /*******************************/
    /* Conects to databases        */
    /*******************************/
   
    GLOBAL $db;
    GLOBAL $admin_email;
   


    if($id == 0)  //database 1
    {
        mysql_select_db("*dbname*", $db)or die("<b>CRITICAL ERROR</b>: error code: '#F-con0'.<BR>Please report this to an admin at $admin_email.".mysql_error());
    }
    elseif($id == 1) // database 2
    {
        mysql_select_db("*dbname*", $db)or die("<b>CRITICAL ERROR</b>: error code: '#F-con1'.<BR>Please report this to an admin at $admin_email.".mysql_error());
    }
    else // no such database
    {
      die("<b>CRITICAL ERROR</b>: error code: '#F-Unk0'.<BR>Please report this to an admin at $admin_email.");
    }
}[/code]

i am calling it like...

[code]mysql_query($sql, CDB(1))[/code]

but i know that isnt right.. and i cant seem to figgure this one out  ???

[hvle]

what you are calling is wrong.  mysql_query take 1st arg as a query, and second arg as database link.  Therefore, function CDB() should return a link in order for mysql_query to work.

so my suggestion for your problem, is change CDB function so that it connect to db, select appropriate schema, and return that link.

something like this:

$dblink = mysql_connect(argvs here);

if (condition)
mysql_select_db(this db);
else mysql_select_db( that db);

return $dblink;

It must return a link.

[leeming]

not fully following.. ive tried a few things... keep editing the code.. managed to get it 2 work, but had to call the function before a query..

ne way i return the selectDB i get..

[quote]Warning: mysql_select_db(): supplied argument is not a valid MySQL-Link resource in /home/.......[/quote]

where the code is

[code]return mysql_select_db("sector_wars", $db)[/code]

[hvle]

you got that error because the $db is not a valid database link.  (did you connect to database?)

i see you do
GLOBAL $db;
GLOBAL $admin_email;

you must make sure $db is a valid link before global.
if you connect to database inside the function, you do not global the connection $db.

[leeming]

$db is the conection info yes, removing it as global doesnt change the error i have...



i have thought away of doing it, but just wonder'd if there was a more simple way of doing it... (and easier for other people to read my code)

basic structure of the new function..
[code]
function newFunction ($sql, $db)
{
  *do selection for databases, using db as a name or id*
      *then connect to data base and connection*

    $outPut = mysql_query($sql, $conection);

    close conection

  return $outPut;

}
[/code]

called as...

[code]
$sql = "select * from table";
$result = callfunction($sql, main database);
[/code]


like i said.. seems a bit messy, and hard for other people to read, as they would be expecting mysql_query() ???

[hvle]

This is very simple problem.  Why don't you tell us what you wanted to do.  Document out the function's responsibilty, and we can suggest a coding structure for it.

[quote]
*do selection for databases, using db as a name or id*
*then connect to data base and connection*
[/quote]
This is a no-go.  You must successfully connected to database before you can select a database (schema).

[leeming]

[quote author=hvle link=topic=100745.msg398016#msg398016 date=1153021628]
This is very simple problem.  Why don't you tell us what you wanted to do.  Document out the function's responsibilty, and we can suggest a coding structure for it.

[quote]
*do selection for databases, using db as a name or id*
*then connect to data base and connection*
[/quote]
This is a no-go.  You must successfully connected to database before you can select a database (schema).


[/quote]
im just very stessed out 2night, thus not been able to think stright (been trying to fix this for hours)

basicly all im trying to do is, make it so i can have 2 database (both same connection details) just different names...

so lets say there is 1 query that needs to use database 1, instead of having

conection -> select db -> query -> close conection

every time i want to do a query... i could just instead choose the database while doing the mysql_query();

[hvle]

try this block of function, fill out the neccessary information:
[code]
function my_db_selection($num)
{
    // connect to your db here
    $dblink = mysql_connect(argv here);
    // do a error handling here if $dblink is null

    // select schema:
    if ($num == 0)
        mysql_select_db('databasename0', $dblink); // fill in the name
    else if ($num == 1)
        mysql_select_db('databasename1', $dblink);
    else {
        echo 'invalid database selection';
        exit();
    }
   
    return $dblink;
}
[/code]

then you can call a query like this:
mysql_query($sql, my_db_selection(0));

[leeming]

[quote author=hvle link=topic=100745.msg398024#msg398024 date=1153022236]
try this block of function, fill out the neccessary information:
[code]
function my_db_selection($num)
{
    // connect to your db here
    $dblink = mysql_connect(argv here);
    // do a error handling here if $dblink is null

    // select schema:
    if ($num == 0)
        mysql_select_db('databasename0', $dblink); // fill in the name
    else if ($num == 1)
        mysql_select_db('databasename1', $dblink);
    else {
        echo 'invalid database selection';
        exit();
    }
   
    return $dblink;
}
[/code]

then you can call a query like this:
mysql_query($sql, my_db_selection(0));
[/quote]

Thanks alot! i knew i was close with what i had.... yup i can finaly goto bed, now that its out o f the way lol