stats: reduce conflict for updating column size #7124
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coocood
reviewed
Jul 23, 2018
statistics/update.go
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| if err != nil { | ||
| return | ||
| } | ||
| values = append(values, fmt.Sprintf("(%d, 0, %d, 0, %d)", id, key, val)) |
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The val is delta, we need to insert the new value.
coocood
reviewed
Jul 23, 2018
statistics/update.go
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| sql := fmt.Sprintf("select * from mysql.stats_histograms where table_id = %d and is_index = 0 for update", id) |
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We should select needed columns instead of * for compatibility.
coocood
reviewed
Jul 23, 2018
statistics/update.go
Outdated
| @@ -344,17 +345,16 @@ func (h *Handle) dumpTableStatColSizeToKV(id int64, delta variable.TableDelta) ( | |||
| err = finishTransaction(ctx, exec, err) | |||
| }() | |||
| version := h.mu.ctx.Txn().StartTS() | |||
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| values := make([]string, 0, len(delta.ColSize)) | |||
| for key, val := range delta.ColSize { | |||
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rename to histID, deltaColSize would be more clear.
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/run-all-tests |
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/run-integration-ddl-test |
alivxxx
added
status/all tests passed
component/statistics
type/enhancement
|
How to know that it is effective? |
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@lamxTyler we need to do a manual test and verify that the conflict is reduced. |
jackysp
approved these changes
Jul 24, 2018
alivxxx
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Jul 24, 2018
coocood
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Jul 24, 2018
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What have you changed? (mandatory)
By using
insert ... on duplicate, we can reduce the possibility of conflict because of less execution time.Fix #7079.
PTAL @coocood @zz-jason @winoros
What is the type of the changes? (mandatory)
How has this PR been tested? (mandatory)
Existing unit test.
Does this PR affect documentation (docs/docs-cn) update? (mandatory)
No.
Does this PR affect tidb-ansible update? (mandatory)
No.
Does this PR need to be added to the release notes? (mandatory)
No.