Represents a generic user-specified index on the given columns. The user provides a function to generate the SQL needed to create
the index based on the table and columns. Validation is required since this is raw SQL being run on the database server.
Represents a generic user-specified index on the given columns. The user provides a function to generate the SQL needed to create the index based on the table and columns. Validation is required since this is raw SQL being run on the database server.