Samarth Jain created PHOENIX-1648: ------------------------------------- Summary: Extra scan being issued while doing SELECT COUNT(*) queries Key: PHOENIX-1648 URL: https://issues.apache.org/jira/browse/PHOENIX-1648 Project: Phoenix Issue Type: Bug Affects Versions: 5.0.0, 4.3 Reporter: Samarth Jain
On turning tracing on and executing SELECT COUNT(*) queries, I am seeing an extra scan being executed every time. CREATE TABLE MY_TABLE (ID INTEGER NOT NULL PRIMARY KEY, VALUE INTEGER) SALT_BUCKETS = 16 SELECT COUNT(*) FROM MY_TABLE The trace table has: Creating basic query for [CLIENT 16-CHUNK PARALLEL 16-WAY FULL SCAN OVER MY_TABLE, SERVER FILTER BY FIRST KEY ONLY, SERVER AGGREGATE INTO SINGLE ROW] Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Parallel scanner for table: MY_TABLE Creating basic query for [CLIENT 1-CHUNK PARALLEL 1-WAY RANGE SCAN OVER SYSTEM.CATALOG [null,null,'MY_TABLE',not null], SERVER FILTER BY COLUMN_FAMILY IS NULL] Parallel scanner for table: SYSTEM.CATALOG While the 16 scanners being created for MY_TABLE is expected, the extra scanner for SYSTEM.CATALOG isn't. This is happening consistently, so this likely isn't happening because of cache expiration. -- This message was sent by Atlassian JIRA (v6.3.4#6332)