[DRILL-6489] Fix filter push down for Hbase & Mapr-DB binary tables when convert function is used in a view

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.13.0
• Fix Version/s: 1.14.0
• Component/s: Storage - HBase, Storage - MapRDB
• Labels: ready-to-commit
• Assignee: Arina Ielchiieva
• Reporter: Arina Ielchiieva
• Reviewer: Vova Vysotskyi
• Created: 12/Jun/18 13:18
• Updated: 13/Jun/18 09:51
• Resolved: 13/Jun/18 09:51

Description

Query

select convert_from(byte_substr(row_key, 1, 8), 'date_epoch_be') as d 
from hbase.`t` 
where convert_from(byte_substr(row_key, 1, 8), date_epoch_be') = date '2015-06-13';

returns plan with the push down:

00-00    Screen
00-01      Project(d=[CONVERT_FROMDATE_EPOCH_BE(BYTE_SUBSTR($0, 1, 8))])
00-02        Scan(groupscan=[HBaseGroupScan [HBaseScanSpec=HBaseScanSpec [tableName=TestTableCompositeDate, startRow=\x00\x00\x01M\xEA7D\x00, stopRow=\x00\x00\x01M\xEF]\xA0\x00, filter=null], columns=[`row_key`]]])

While the same query in a view does not:

create view dfs.tmp.v as select convert_from(byte_substr(row_key, 1, 8), 'date_epoch_be') as d from hbase.`t`;
select d from dfs.tmp.v where d = date '2015-06-13';

00-00    Screen
00-01      Project(d=[CONVERT_FROMDATE_EPOCH_BE(BYTE_SUBSTR($0, 1, 8))])
00-02        SelectionVectorRemover
00-03          Filter(condition=[=(CONVERT_FROMDATE_EPOCH_BE(BYTE_SUBSTR($0, 1, 8)), 2015-06-13)])
00-04            Scan(groupscan=[HBaseGroupScan [HBaseScanSpec=HBaseScanSpec [tableName=TestTableCompositeDate, startRow=null, stopRow=null, filter=null], columns=[`row_key`]]])

The problem that CompareFunctionsProcessor waits for ConvertExpression but receives FunctionCall with convert function. If convert function first appears in filter it is re-presented as ConvertExpression (case without view). If convert function first appears in select is re-presented as FunctionCall for convert function (case with view). The reason of such difference is the appliance of the PreProcessLogicalRel visitor. The solution in this case would be to check FunctionCall in CompareFunctionsProcessor}} and if this function call for convert from function, process it as ConvertExpression.

https://github.com/apache/drill/blob/master/contrib/storage-hbase/src/main/java/org/apache/drill/exec/store/hbase/CompareFunctionsProcessor.java#L171

https://github.com/apache/drill/blob/master/exec/java-exec/src/main/java/org/apache/drill/exec/planner/sql/handlers/DefaultSqlHandler.java#L667

Issue Links

• links to: GitHub Pull Request #1318