GetColsAndSchemas provides information about columns and schema for a table.

ProcessDbDump reads dump data from r and does schema or data conversion, depending on whether conv is configured for schema mode or data mode.

ToNotNull returns true if a column is not nullable and false if it is.

Default to 20 - observed diminishing returns above this value.

Data type sizes are referred from https://cloud.google.com/spanner/docs/reference/standard-sql/data-types#storage_size_for_data_types.

FkConstraint contains foreign key constraints.

SchemaAndName contains the schema and name for a table.

DbDump common interface for database dump functions.

InfoSchema contains database information.

ToDdl interface is meant to be implemented by all sources.