Function: Checks the version of the installed MySQL binary.

Function: Disables the Automattic widgets plugin, which was merged into core.

Function: Disables the Link Manager on upgrade if, at the time of upgrade, no links exist in the DB.

Function: Runs before the schema is upgraded.

Function: Adds an index to a specified table.

Function: If a table only contains utf8 or utf8mb4 columns, convert it to utf8mb4.

Function: Retrieve all options as it was for 1.2.

Function: Filters for content to remove unnecessary slashes.

Function: Modifies the database based on specified SQL statements.

Function: Updates the database tables to a new schema.