I learned MySQL through checking the available functions and how they're used in common gamemode scripts on the site supplied in the MySQL plugin thread in the plugins board, and through googling the main functions of MySQL.
MySQL is a form of saving information, but instead of saving lines in a text file (like fwrite does) it saves information in tables
like this
Код:
Column 1 - Column 2 - Column 3
Row 1| Name | Level | Admin |
Row 2| Name | Level | Admin |
Row 3| Name | Level | Admin |
So instead of doing a check if a player's file exists, you check the table of the player's name already exists, then you just get the rest of the information by checking the other columns of that row.
Example: Player "Jimmy" has logged into the server. Comparing Jimmy's name with those in all of column 1(names), Jimmy's name was found on row 3, checking the levels column to get Jimmy's level, Jimmy is level 5!
That sorta thing... yeah...