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sql: update tidb specific link description #692

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Oct 29, 2018
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sql: update tidb specific link description #692

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sql: update tidb specific link description
morgo Oct 26, 2018
ff9f38f
Remove specific, improve readability
morgo Oct 29, 2018
bd7bb8d
Update specific variables
morgo Oct 29, 2018
2617573
Update tidb-specific.md
morgo Oct 29, 2018
7dce7fb
Update tidb-specific.md
morgo Oct 29, 2018
31258eb
Update tidb-specific.md
morgo Oct 29, 2018
cd9f07b
Update tidb-specific.md
morgo Oct 29, 2018
cd0f566
Update tidb-specific.md
morgo Oct 29, 2018
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Update tidb-specific.md
morgo Oct 29, 2018
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2 changes: 1 addition & 1 deletion sql/tidb-server.md
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Expand Up @@ -14,7 +14,7 @@ You can set the service parameters using the command line or the configuration f

## TiDB system variable

TiDB is compatible with MySQL system variables, and defines some unique system variables to adjust the database behavior. For more information, see [The Proprietary System Variables and Syntaxes in TiDB](../sql/tidb-specific.md).
TiDB is compatible with MySQL system variables, and defines some unique system variables to adjust the database behavior. For more information, see [TiDB Specific System Variables](../sql/tidb-specific.md).

## TiDB system table

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6 changes: 3 additions & 3 deletions sql/tidb-specific.md
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Expand Up @@ -291,9 +291,9 @@ set @@global.tidb_distsql_scan_concurrency = 10

## Optimizer Hint

On the basis of MySQL’s `Optimizer Hint` Syntax, TiDB adds some proprietary `Hint` syntaxes. When using the `Hint` syntax, the TiDB optimizer will try to use the specific algorithm, which performs better than the default algorithm in some scenarios.
The `Hint` syntax is included in comments like `/*+ xxx */`, and in MySQL client versions earlier than 5.7.7, the comment is removed by default. If you want to use the `Hint` syntax in these earlier versions, add the `--comments` option when starting the client. For example: `mysql -h 127.0.0.1 -P 4000 -uroot --comments`.
TiDB supports optimizer hints, based on the format of the comment-like syntax introduced in MySQL 5.7. i.e. `/*+ TIDB_XX(t1, t2) */`. Use of optimizer hints is recommended in cases where the TiDB optimizer selects a less optimal query plan.

**Note:** MySQL command-line clients earlier than 5.7.7 will strip optimizer hints by default. If you want to use the `Hint` syntax in these earlier versions, add the `--comments` option when starting the client. For example: `mysql -h 127.0.0.1 -P 4000 -uroot --comments`.
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  • For a Note, please use this format > **Note:**.
  • will strip -> strip (Please limit the use of the future tense where possible.)

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Thx. I've updated this, and also changed the titles to plural (since there is more than one hint and more than one variable).

Let me know if this is a problem


### TIDB_SMJ(t1, t2)

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4 changes: 2 additions & 2 deletions sql/variable.md
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Expand Up @@ -45,6 +45,6 @@ The following MySQL system variables are fully supported in TiDB and have the sa
| tx_isolation | GLOBAL \| SESSION | the isolation level of a transaction |
| hostname | NONE | the hostname of the TiDB server |

## The proprietary system variables and syntaxes in TiDB
## TiDB Specific System Variables

See [The Proprietary System Variables and Syntax in TiDB](../sql/tidb-specific.md).
See [TiDB Specific System Variables](../sql/tidb-specific.md).