# Functions
Query executes a query.
Read reads all rows from the given table.
Write writes the elements of the given PCollection<T> to database, if columns left empty all table columns are used to insert into, otherwise selected.
WriteWithBatchSize writes the elements of the given PCollection<T> to database with custom batch size.
# Interfaces
MapLoader calls on LoadMap method with with a fetched row as map.
SliceLoader calls LoadSlice method with a fetched row as slice.
Writer returns a row of data to be inserted into a table.