If a column is at the constrained limit like mdl_log - url, then if you replace it with a new url larger, that the search url will fail.

Error writing to database

More information about this error

Debug info: ERROR: value too long for type character varying(100)

UPDATE mdl_log SET url = REPLACE(url, $1, $2)

[array (

0 => 'http://localhost/moodle',

1 => 'http://localhost/moodle21',

)]

Stack trace:

line 397 of /lib/dml/moodle_database.php: dml_write_exception thrown

line 232 of /lib/dml/pgsql_native_moodle_database.php: call to moodle_database->query_end()

line 596 of /lib/dml/pgsql_native_moodle_database.php: call to pgsql_native_moodle_database->query_end()

line 6281 of /lib/adminlib.php: call to pgsql_native_moodle_database->execute()

line 47 of /admin/replace.php: call to db_replace()

Jason Ilicic and I have made some fixes to the db_replace() function to fix database issues when running it.

• Running the replace command on fields that don't have the search url in it.
  • In PostgreSQL, update creates another row and tags the old row was re-usable but effectively doubling the Database size.
• Replacing a URL that is greater than original and making the column larger that DB constraints.
  • If column is 100 chars (mdl_log - url) and data is 100 chars, an update will fail if replace url is greater that search url.
• Replace the search url if the column is equal or greater that the size of the search url.