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DB layer 2.0

From MoodleDocs

Moodle 2.0


  • Switch to prepared statements - using placeholders and preparing statements protects against sql injection
  • Remove the need for data to be add/strip slashed all over the place in the code.
  • Enable easier and productive unit tests.


  • 100% cross-db
  • OOP implementation:
    • Full abstraction: Hide underlying libraries (adodb, pdo...) and drivers to Moodle developers completely.
    • Make it so that the database object can be subclassed - this means for unit tests that want to test database access, the test framework can override necessary methods
    • support ? and :param parameter types (independently of the param types supported by each driver).
    • global $DB
    • profiling, logging and exceptions
  • Easy to use (consistent and similar to current dmllib 1.0)
  • Easy to migrate (provide documentation and utilities to help on that)
  • Complete unit testing (self)
  • Easy unit testing (moodle - real and mockup)
  • Well documented (PHPDocs + use examples)
  • Tasks, bugs and progress tracked in MDL-14679
  • Due date: June 24th 2008

See also

  • XMLDB Documentation: where both xmldb and ddl stuff is explained.
  • DDL functions - Documentation for all the Data Definition Language (DDL) functions available inside Moodle.
  • DML functions - Documentation for all the Data Manipulation Language (DML) functions available inside Moodle.