Istvan Toth created PHOENIX-6797: ------------------------------------ Summary: Optimize rowkey prefix selects for salted tables Key: PHOENIX-6797 URL: https://issues.apache.org/jira/browse/PHOENIX-6797 Project: Phoenix Issue Type: Bug Components: core Reporter: Istvan Toth
For a salted table with a composite PK, queries using a PK prefix are turned into basically full scans. We should scan only the salt key + PK prefix range for each key. i.e we have the salted table {noformat} CREATE TABLE T (ID1 VARCHAR(64) not null, ID2 VARCHAR(15) not null, ID3 VARCHAR(24), V1 DATE, CONSTRAINT pk PRIMARY KEY (ID1, ID2, ID3)) SALT_BUCKETS = 31;{noformat} and we do a select based on ID1: {noformat} select * from T where id1='whatever';{noformat} Phoenix will do a range scan over the following, which is basically a full scan. [0,'whatever'] - [30,'whatever'] However, we only really need to scan the far smaller {noformat} [0,'whatever'] - [0,'whateves'] ,[1,'whatever'] - [1,'whateves'] .. ,[30,'whatever'] - [30,'whateves']{noformat} ranges. -- This message was sent by Atlassian Jira (v8.20.10#820010)