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Version: 4.5

DML exceptions

Newer Version Available
This documentation is for Moodle 4.5.
You may also want to read the documentation for the upcoming version of Moodle.

The DML API uses a selection of exceptions to indicate errors.

Types of exception​

DML Exceptions

dml_connection_exception​

Thrown when can not connect to database for any reason.

dml_read_exception​

Problem occurred during reading from database. Originally indicated be returning false - this value was often confused with false return value meaning not found.

dml_write_exception​

Problem occurred during writing to database. Originally indicated be returning false.

See also​

  • Exceptions: General guidelines for using of exceptions in Moodle 2.0
  • DML functions: Where all the functions used to handle DB data. (DML) are defined.
  • DDL functions: Where all the functions used to handle DB objects (DDL) are defined.