Details
-
Bug
-
Status: Stalled (View Workflow)
-
Minor
-
Resolution: Unresolved
-
10.2(EOL), 10.3(EOL), 10.4(EOL), 10.5, 10.6, 10.7(EOL)
-
None
Description
--source include/have_sequence.inc
|
|
CREATE TABLE t (a VARCHAR(16) COMPRESSED COLLATE ucs2_sinhala_ci); |
INSERT INTO t SELECT REPEAT(CHR(seq%26+97),16) FROM seq_1_to_100; |
|
set histogram_type= DOUBLE_PREC_HB; |
analyze table t persistent for all; |
ANALYZE FORMAT=JSON SELECT a FROM t WHERE 'c' BETWEEN 'l' AND a ; |
|
set histogram_type= JSON_HB; |
analyze table t persistent for all; |
ANALYZE FORMAT=JSON SELECT a FROM t WHERE 'c' BETWEEN 'l' AND a ; |
|
# Cleanup
|
DROP TABLE t; |
DOUBLE_PREC_HB preview-10.8-MDEV-26519-json-histograms 21a81025 |
"table": { |
"table_name": "t", |
"access_type": "ALL", |
"r_loops": 1, |
"rows": 100, |
"r_rows": 100, |
"r_table_time_ms": 0.006661524, |
"r_other_time_ms": 0.006350519, |
"filtered": 3.846199989, |
"r_filtered": 0, |
"attached_condition": "'c' between 'l' and t.a" |
}
|
JSON_HB |
"table": { |
"table_name": "t", |
"access_type": "ALL", |
"r_loops": 1, |
"rows": 100, |
"r_rows": 100, |
"r_table_time_ms": 0.005778671, |
"r_other_time_ms": 0.005598088, |
"filtered": 93, |
"r_filtered": 0, |
"attached_condition": "'c' between 'l' and t.a" |
}
|
The actual result set is naturally empty. So, DOUBLE_PREC is close, JSON is far away.
Reproducible with at least MyISAM, InnoDB, Aria.
Attachments
Issue Links
- is caused by
-
MDEV-26519 JSON Histograms: improve histogram collection
- Closed