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Posted to issues@flink.apache.org by GitBox <gi...@apache.org> on 2021/01/26 12:16:55 UTC
[GitHub] [flink] fsk119 commented on a change in pull request #14710: [FLINK-19393][docs-zh] Translate the 'SQL Hints' page of 'Table API & SQL' into Chinese
fsk119 commented on a change in pull request #14710:
URL: https://github.com/apache/flink/pull/14710#discussion_r564455050
##########
File path: docs/dev/table/sql/hints.zh.md
##########
@@ -63,24 +54,25 @@ val:
{% endhighlight %}
-### Examples
+<a name="examples"></a>
+### 示例
{% highlight sql %}
CREATE TABLE kafka_table1 (id BIGINT, name STRING, age INT) WITH (...);
CREATE TABLE kafka_table2 (id BIGINT, name STRING, age INT) WITH (...);
--- override table options in query source
+-- 在查询源中覆盖表选项
Review comment:
覆盖查询语句中源表的选项
##########
File path: docs/dev/table/sql/hints.zh.md
##########
@@ -63,24 +54,25 @@ val:
{% endhighlight %}
-### Examples
+<a name="examples"></a>
+### 示例
{% highlight sql %}
CREATE TABLE kafka_table1 (id BIGINT, name STRING, age INT) WITH (...);
CREATE TABLE kafka_table2 (id BIGINT, name STRING, age INT) WITH (...);
--- override table options in query source
+-- 在查询源中覆盖表选项
select id, name from kafka_table1 /*+ OPTIONS('scan.startup.mode'='earliest-offset') */;
--- override table options in join
+-- 在 join 中覆盖表选项
select * from
kafka_table1 /*+ OPTIONS('scan.startup.mode'='earliest-offset') */ t1
join
kafka_table2 /*+ OPTIONS('scan.startup.mode'='earliest-offset') */ t2
on t1.id = t2.id;
--- override table options for INSERT target table
+-- 对 INSERT 目标表使用覆盖表选项
Review comment:
覆盖插入语句中结果表的选项
##########
File path: docs/dev/table/sql/hints.zh.md
##########
@@ -63,24 +54,25 @@ val:
{% endhighlight %}
-### Examples
+<a name="examples"></a>
+### 示例
{% highlight sql %}
CREATE TABLE kafka_table1 (id BIGINT, name STRING, age INT) WITH (...);
CREATE TABLE kafka_table2 (id BIGINT, name STRING, age INT) WITH (...);
--- override table options in query source
+-- 在查询源中覆盖表选项
select id, name from kafka_table1 /*+ OPTIONS('scan.startup.mode'='earliest-offset') */;
--- override table options in join
+-- 在 join 中覆盖表选项
Review comment:
覆盖 join 中源表的选项
##########
File path: docs/dev/table/sql/hints.zh.md
##########
@@ -25,34 +25,25 @@ under the License.
* This will be replaced by the TOC
{:toc}
-SQL hints can be used with SQL statements to alter execution plans. This chapter explains how to use hints to force various approaches.
-
-Generally a hint can be used to:
-
-- Enforce planner: there's no perfect planner, so it makes sense to implement hints to
-allow user better control the execution;
-- Append meta data(or statistics): some statistics like “table index for scan” and
-“skew info of some shuffle keys” are somewhat dynamic for the query, it would be very
-convenient to config them with hints because our planning metadata from the planner is very
-often not that accurate;
-- Operator resource constraints: for many cases, we would give a default resource
-configuration for the execution operators, i.e. min parallelism or
-managed memory (resource consuming UDF) or special resource requirement (GPU or SSD disk)
-and so on, it would be very flexible to profile the resource with hints per query(instead of the Job).
-
-## Dynamic Table Options
-Dynamic table options allows to specify or override table options dynamically, different with static table options defined with SQL DDL or connect API,
-these options can be specified flexibly in per-table scope within each query.
-
-Thus it is very suitable to use for the ad-hoc queries in interactive terminal, for example, in the SQL-CLI,
-you can specify to ignore the parse error for a CSV source just by adding a dynamic option `/*+ OPTIONS('csv.ignore-parse-errors'='true') */`.
-
-<b>Note:</b> Dynamic table options default is forbidden to use because it may change the semantics of the query.
-You need to set the config option `table.dynamic-table-options.enabled` to be `true` explicitly (default is false),
-See the <a href="{% link dev/table/config.zh.md %}">Configuration</a> for details on how to set up the config options.
-
-### Syntax
-In order to not break the SQL compatibility, we use the Oracle style SQL hint syntax:
+可以将 SQL 提示（hints）与 SQL 语句一起使用改变执行计划（execution plans）。本章介绍如何使用 SQL 提示增强各种方法。
+
+SQL 提示一般可以用于以下：
+
+- Enforce planner：没有十分契合的 planner，所以实现提示让用户更好地控制执行是十分有意义的；
+- 增加元数据（或者统计信息）：如 "table index for scan" 和 "skew info of some shuffle keys" 的一些统计数据对于查询来说是动态的，用提示来配置它们会非常方便，因为我们从 planner 获得的计划元数据通常不那么准确；
Review comment:
Please also translate the "table index for scan" and "skew info of some shuffle keys".
##########
File path: docs/dev/table/sql/hints.zh.md
##########
@@ -25,34 +25,25 @@ under the License.
* This will be replaced by the TOC
{:toc}
-SQL hints can be used with SQL statements to alter execution plans. This chapter explains how to use hints to force various approaches.
-
-Generally a hint can be used to:
-
-- Enforce planner: there's no perfect planner, so it makes sense to implement hints to
-allow user better control the execution;
-- Append meta data(or statistics): some statistics like “table index for scan” and
-“skew info of some shuffle keys” are somewhat dynamic for the query, it would be very
-convenient to config them with hints because our planning metadata from the planner is very
-often not that accurate;
-- Operator resource constraints: for many cases, we would give a default resource
-configuration for the execution operators, i.e. min parallelism or
-managed memory (resource consuming UDF) or special resource requirement (GPU or SSD disk)
-and so on, it would be very flexible to profile the resource with hints per query(instead of the Job).
-
-## Dynamic Table Options
-Dynamic table options allows to specify or override table options dynamically, different with static table options defined with SQL DDL or connect API,
-these options can be specified flexibly in per-table scope within each query.
-
-Thus it is very suitable to use for the ad-hoc queries in interactive terminal, for example, in the SQL-CLI,
-you can specify to ignore the parse error for a CSV source just by adding a dynamic option `/*+ OPTIONS('csv.ignore-parse-errors'='true') */`.
-
-<b>Note:</b> Dynamic table options default is forbidden to use because it may change the semantics of the query.
-You need to set the config option `table.dynamic-table-options.enabled` to be `true` explicitly (default is false),
-See the <a href="{% link dev/table/config.zh.md %}">Configuration</a> for details on how to set up the config options.
-
-### Syntax
-In order to not break the SQL compatibility, we use the Oracle style SQL hint syntax:
+可以将 SQL 提示（hints）与 SQL 语句一起使用改变执行计划（execution plans）。本章介绍如何使用 SQL 提示增强各种方法。
Review comment:
I think it's better to not translate the word `hints`. After I search with key words `sql hints` in baidu.com, I get more results about auto complete.
I think it's better to translate to
```
SQL hints 是和SQL语句一起使用来改变执行计划的。
```
##########
File path: docs/dev/table/sql/hints.zh.md
##########
@@ -25,34 +25,25 @@ under the License.
* This will be replaced by the TOC
{:toc}
-SQL hints can be used with SQL statements to alter execution plans. This chapter explains how to use hints to force various approaches.
-
-Generally a hint can be used to:
-
-- Enforce planner: there's no perfect planner, so it makes sense to implement hints to
-allow user better control the execution;
-- Append meta data(or statistics): some statistics like “table index for scan” and
-“skew info of some shuffle keys” are somewhat dynamic for the query, it would be very
-convenient to config them with hints because our planning metadata from the planner is very
-often not that accurate;
-- Operator resource constraints: for many cases, we would give a default resource
-configuration for the execution operators, i.e. min parallelism or
-managed memory (resource consuming UDF) or special resource requirement (GPU or SSD disk)
-and so on, it would be very flexible to profile the resource with hints per query(instead of the Job).
-
-## Dynamic Table Options
-Dynamic table options allows to specify or override table options dynamically, different with static table options defined with SQL DDL or connect API,
-these options can be specified flexibly in per-table scope within each query.
-
-Thus it is very suitable to use for the ad-hoc queries in interactive terminal, for example, in the SQL-CLI,
-you can specify to ignore the parse error for a CSV source just by adding a dynamic option `/*+ OPTIONS('csv.ignore-parse-errors'='true') */`.
-
-<b>Note:</b> Dynamic table options default is forbidden to use because it may change the semantics of the query.
-You need to set the config option `table.dynamic-table-options.enabled` to be `true` explicitly (default is false),
-See the <a href="{% link dev/table/config.zh.md %}">Configuration</a> for details on how to set up the config options.
-
-### Syntax
-In order to not break the SQL compatibility, we use the Oracle style SQL hint syntax:
+可以将 SQL 提示（hints）与 SQL 语句一起使用改变执行计划（execution plans）。本章介绍如何使用 SQL 提示增强各种方法。
+
+SQL 提示一般可以用于以下：
+
+- Enforce planner：没有十分契合的 planner，所以实现提示让用户更好地控制执行是十分有意义的；
Review comment:
enforce planner -> 增强planner
perfect -> 完美。
实现提示让用户 -> 通过提示，用户
这里主要是表达 任何优化都可能有bad case，需要人手动优化。
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