CREATE TABLE.md

Original Method

1. HiveMetaStoreClient#createTable: Set the default catalog, set processor capabilities or else, and hook.preCreateTable
2. SessionHiveMetaStoreClient#create_table: Bail out and create a temporary table if the give table is temporary
3. HiveMetaStoreClient#create_table: Issue a Thrift request
4. HiveMetaStoreClient#createTable: hook.CommitCreateTable

New Method

From the outmost wrapper,

1. HiveMetaStoreClientWithHook: hook.preCreateTable
2. HiveMetaStoreClientWithTmpTable: Bail out and create a temporary table if the given table is temporary
3. HiveMetaStoreClientWithSessionFeature: Do nothing
4. HiveMetaStoreClientWithLocalCache: Do nothing
5. ThriftHiveMetaStoreClient: Set the default catalog name, set processor capabilities or else, and then issue a Thrift client
6. HiveMetaStoreClientWithHook: hook.commitCreateTable

Comparison

Order	Original	New
1	Set the default catalog	hook.preCreateTable
2	Set processor capabilities	Tmp table handling
3	hook.preCreateTable	Set the default catalog
4	Tmp table handling	Set processor capabilities
5	Thrift request	Thrift request
6	hook.CommitCreateTable	hook.CommitCreateTable

• The original implementation fills a catalog name or processor capabilities at a very early stage, so HiveMetaHook or another part can see the values

GET TABLE.md

Original Method

1. SessionHiveMetaStoreClient#getTable: Return a temp table if it exists
2. HiveMetaStoreClient#getTable: Set the default catalog name, set processor capabilities
3. SessionHiveMetaStoreClient#getTableInternal: Query cache handling
4. HiveMetaStoreClientWithLocalCache#getTableInternal: HS2 cache handling
5. HiveMetaStoreClient#getTableInternal: Issue a Thrift request
6. HiveMetaStoreClient#getTable: HiveMetaHook#postGetTable, MetaStoreFilterHook#filterTable

New Method

1. HiveMetaStoreClientWithHook#getTable: Set the default catalog
2. HiveMetaStoreClientWithTmpTable#getTable: Temp table handling
3. HiveMetaStoreClientWithSessionFeature#getTable Set the default catalog, query cache handling
4. HiveMetaStoreClientWithLocalCache#getTable: Set the default catalog, HS2 cache handling
5. ThriftHiveMetaStoreClient:getTable: Set the default catalog, processor capabilities, Issue a Thrift request
6. HiveMetaStoreClientWithHook#getTable: HiveMetaHook#postGetTable, MetaStoreFilterHook#filterTable

Comparison

Order	Original	New
1	Tmp table handling	Set the default catalog
2	Set the default catalog	Tmp table handling
3	Set processor capabilities	Set the default catalog
4	Query cache handling	Query cache handling
5	HS2 cache handling	HS2 cache handling
6	Thrift request	Set the default catalog
7	HiveMetaHook#postGetTable	Set processor capabilities
8	MetaStoreFilterHook#filterTable	Thrift request
9	N/A	HiveMetaHook#postGetTable
10	N/A	MetaStoreFilterHook#filterTable

• The timing setting processor capabilities are different
• IMetaStoreClient#getTable is highly overloaded. Do we have to implement many in each delegation?