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bug: using Like in secondary index don't use index

Open gayratv opened this issue 2 years ago • 1 comments

YDB serverless

Use this table:

CREATE TABLE my_table (
    k1 Uint32,
    k2 Uint64,
    desc Utf8,
    index my_tbl_ind global on(desc),
    PRIMARY KEY (k1,k2)
);
commit;
insert into my_table (k1,k2,desc)
values
(1u,1ul,'desc 11'u),
(2u,2ul,'desc 22'u),
(3u,3ul,'desc 33'u),
(4u,4ul,'desc 44'u),
(5u,5ul,'desc 55'u);
commit;

This query don't using secondary index (as described in docs) and generate FullScan

SELECT * FROM my_table view my_tbl_ind  WHERE desc like 'desc 1%'u

gayratv avatar Apr 24 '22 19:04 gayratv

I suppose it's all about selecting a query plan, that uses indexes automatically.

fomichev3000 avatar May 18 '22 09:05 fomichev3000