[MCOL-4288] create table ..select * from table... Created: 2020-09-02  Updated: 2021-04-19  Resolved: 2020-12-29

Status: Closed
Project: MariaDB ColumnStore
Component/s: N/A
Affects Version/s: 1.5.3
Fix Version/s: N/A

Type: Bug Priority: Major
Reporter: Richard Stracke Assignee: Todd Stoffel (Inactive)
Resolution: Not a Bug Votes: 0
Labels: None

Attachments: File p1.sql    

 Description   

MariaDB 10.5.5 single server.

create table t2 engine=columnstore... select * from t1

(regardless if t1 is innodb or columnstore)

is still slow.

100 rows / 80 columns in my tests take 8 minutes.
The same with t2 as innodb take a couple of seconds.

This is linear.

200 rows / 80 columns rows take 16 minutes.

199 row / 40 columns take 4 minutes.

Innodb on the same machine take 4 seconds.

A testcase with testdata is attached (p1.sql)

 Comments   
Comment by Todd Stoffel (Inactive) [ 2020-12-29 ]

This is an unsupported function of Columnstore. This should be done in two steps instead.

create table t2 engine=columnstore as select * from t1 limit 0;
 
insert into t2 select * from t1;

Generated at Thu Feb 08 02:49:14 UTC 2024 using Jira 8.20.16#820016-sha1:9d11dbea5f4be3d4cc21f03a88dd11d8c8687422.