ddl, config: add a variable to control the max index length #15012
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
zimulala
added
type/compatibility
priority/release-blocker
Codecov Report
@@ Coverage Diff @@
## master #15012 +/- ##
===========================================
Coverage ? 80.2819%
===========================================
Files ? 502
Lines ? 131458
Branches ? 0
===========================================
Hits ? 105537
Misses ? 17553
Partials ? 8368 |
tangenta
reviewed
Mar 2, 2020
config/config.go
Outdated
| // DefMaxIndexLength is the maximum index length. This value is consistent with MySQL. | ||
| DefMaxIndexLength = 3072 | ||
| // DefTiDBMaxIndexLength is the maximum index length for TiDB v3.0.7 and previous version. | ||
| DefTiDBMaxIndexLength = 3072 * 4 |
There was a problem hiding this comment.
In the old implementation, the index length was not in bytes, but in characters.
That means if we set max-index-length to 12288 (3072 * 4), the following statement is valid in current PR but it is invalid in TiDB v3.0.7-.
create table t12 (a varchar(12288) character set ascii primary key);Is it acceptable?
There was a problem hiding this comment.
It is acceptable.
We want to make the following statement is valid in current TiDB like in TiDB v3.0.7-.
create table t12 (a varchar(3072) character set utf8mb4 primary key);
djshow832
reviewed
Mar 2, 2020
zimulala
added
require-LGT3
djshow832
reviewed
Mar 2, 2020
zimulala
added
status/can-merge
|
/run-all-tests |
sre-bot
pushed a commit
to sre-bot/tidb
that referenced
this pull request
Mar 2, 2020
Signed-off-by: sre-bot <sre-bot@pingcap.com>
|
cherry pick to release-3.0 in PR #15057 |
sre-bot
added a commit
that referenced
this pull request
Mar 2, 2020
sre-bot
pushed a commit
to sre-bot/tidb
that referenced
this pull request
Mar 3, 2020
Signed-off-by: sre-bot <sre-bot@pingcap.com>
|
cherry pick to release-4.0 in PR #15083 |
5 tasks
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
What problem does this PR solve?
Before #13727(v3.0.8):
After #13727:
Therefore, in v3.0.8 and after, such statements will report an error, which is not compatible with the behavior of versions before v3.0.8.
What is changed and how it works?
Add a variable to control the max index length. And the value range is [3072, 3072*4].
The default value is 3072, it is consistent with MySQL.
Check List
Tests
Related changes
Release note