org.apache.drill.metastore.rdbms.transform

Interface MetadataMapper<U,R extends org.jooq.Record>

Type Parameters:

U - Metastore component metadata type

R - RDBMS table record type

All Known Implementing Classes:

AbstractMetadataMapper, TablesMetadataMapper, TablesMetadataMapper.FileMapper, TablesMetadataMapper.PartitionMapper, TablesMetadataMapper.RowGroupMapper, TablesMetadataMapper.SegmentMapper, TablesMetadataMapper.TableMapper

public interface MetadataMapper<U,R extends org.jooq.Record>

Provides various mapping, transformation methods for the given RDBMS table and Metastore component metadata unit.

Method Summary

Modifier and Type	Method and Description
U	emptyUnit()
org.jooq.Table<R>	table()
org.jooq.Condition	toCondition(FilterExpression filter) Converts Metastore filter expression into JOOQ condition instance which will be used as where clause in SQL query.
List<org.jooq.Condition>	toDeleteConditions(List<U> units) Since data in Metastore is deleted by partition, extracts partitions values from given list of Metastore component metadata units and creates list of delete conditions based on them.
List<org.jooq.Field<?>>	toFields(List<MetastoreColumn> columns) Matches given list of Metastore columns to the available RDBMS table columns.
R	toRecord(U unit) Converts Metastore component metadata unit into RDBMS table record.
U	toUnit(org.jooq.Record record) Converts RDBMS table record into Metastore component metadata unit.

Method Detail

table

org.jooq.Table<R> table()

Returns:

RDBMS table instance

emptyUnit

U emptyUnit()

Returns:

Metastore component metadata unit instance with all fields set to null

toUnit

U toUnit(org.jooq.Record record)

Converts RDBMS table record into Metastore component metadata unit.

Parameters:

record - RDBMS table record

Returns:

Metastore component metadata unit instance

toRecord

R toRecord(U unit)

Converts Metastore component metadata unit into RDBMS table record.

Parameters:

unit - Metastore component metadata unit

Returns:

RDBMS table record instance

toFields

List<org.jooq.Field<?>> toFields(List<MetastoreColumn> columns)

Matches given list of Metastore columns to the available RDBMS table columns.

Parameters:

columns - list of Metastore columns

Returns:

list of RDBMS table fields

toCondition

org.jooq.Condition toCondition(FilterExpression filter)

Converts Metastore filter expression into JOOQ condition instance which will be used as where clause in SQL query.

Parameters:

filter - filter expression

Returns:

JOOQ condition instance

toDeleteConditions

List<org.jooq.Condition> toDeleteConditions(List<U> units)

Since data in Metastore is deleted by partition, extracts partitions values from given list of Metastore component metadata units and creates list of delete conditions based on them.

Parameters:

units - list of Metastore component metadata units

Returns:

list of JOOQ condition instances