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Posted to commits@doris.apache.org by yi...@apache.org on 2023/11/30 09:27:46 UTC
(doris) branch master updated: [doc](partial update) update suggestions of using unique key table (#27810)
This is an automated email from the ASF dual-hosted git repository.
yiguolei pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/doris.git
The following commit(s) were added to refs/heads/master by this push:
new 9d2aac305f5 [doc](partial update) update suggestions of using unique key table (#27810)
9d2aac305f5 is described below
commit 9d2aac305f515c48d932981757ce17408f92e4f3
Author: zhannngchen <48...@users.noreply.github.com>
AuthorDate: Thu Nov 30 17:27:39 2023 +0800
[doc](partial update) update suggestions of using unique key table (#27810)
---
docs/en/docs/data-table/data-model.md | 5 ++---
docs/zh-CN/docs/data-table/data-model.md | 5 ++---
2 files changed, 4 insertions(+), 6 deletions(-)
diff --git a/docs/en/docs/data-table/data-model.md b/docs/en/docs/data-table/data-model.md
index 4e6cae8c668..12af334e961 100644
--- a/docs/en/docs/data-table/data-model.md
+++ b/docs/en/docs/data-table/data-model.md
@@ -791,7 +791,6 @@ but not unique identifiers. In Aggregate and Unique Models, the Key columns are
Since the data model was established when the table was built, and **irrevocable thereafter, it is very important to select the appropriate data model**.
1. The Aggregate Model can greatly reduce the amount of data scanned and query computation by pre-aggregation. Thus, it is very suitable for report query scenarios with fixed patterns. But this model is unfriendly to `count (*)` queries. Meanwhile, since the aggregation method on the Value column is fixed, semantic correctness should be considered in other types of aggregation queries.
-2. The Unique Model guarantees the uniqueness of primary key for scenarios requiring a unique primary key. The downside is that it cannot exploit the advantage brought by pre-aggregation such as ROLLUP in queries.
- 1. Users who have high-performance requirements for aggregate queries are recommended to use the newly added Merge on Write implementation since version 1.2.
- 2. The Unique Model only supports entire-row updates. If you require primary key uniqueness as well as partial updates of certain columns (such as loading multiple source tables into one Doris table), you can consider using the Aggregate Model, while setting the aggregate type of the non-primary key columns to REPLACE_IF_NOT_NULL. See [CREATE TABLE Manual](../sql-manual/sql-reference/Data-Definition-Statements/Create/CREATE-TABLE.md) for more details.
+2. The Unique Model guarantees the uniqueness of primary key for scenarios requiring a unique primary key. The downside is that it cannot exploit the advantage brought by pre-aggregation such as ROLLUP in queries. Users who have high-performance requirements for aggregate queries are recommended to use the newly added Merge on Write implementation since version 1.2.
3. The Duplicate Model is suitable for ad-hoc queries of any dimensions. Although it may not be able to take advantage of the pre-aggregation feature, it is not limited by what constrains the Aggregate Model and can give full play to the advantage of columnar storage (reading only the relevant columns, but not all Key columns).
+4. If user need to use partial-update, please refer to documnet [partial-update](../data-operate/update-delete/partial-update.md)
diff --git a/docs/zh-CN/docs/data-table/data-model.md b/docs/zh-CN/docs/data-table/data-model.md
index e3bff1d29ee..3e2b8ed2e60 100644
--- a/docs/zh-CN/docs/data-table/data-model.md
+++ b/docs/zh-CN/docs/data-table/data-model.md
@@ -787,7 +787,6 @@ Duplicate、Aggregate、Unique 模型，都会在建表指定 key 列，然而
因为数据模型在建表时就已经确定，且**无法修改**。所以，选择一个合适的数据模型**非常重要**。
1. Aggregate 模型可以通过预聚合，极大地降低聚合查询时所需扫描的数据量和查询的计算量，非常适合有固定模式的报表类查询场景。但是该模型对 count(*) 查询很不友好。同时因为固定了 Value 列上的聚合方式，在进行其他类型的聚合查询时，需要考虑语意正确性。
-2. Unique 模型针对需要唯一主键约束的场景，可以保证主键唯一性约束。但是无法利用 ROLLUP 等预聚合带来的查询优势。
- 1. 对于聚合查询有较高性能需求的用户，推荐使用自1.2版本加入的写时合并实现。
- 2. Unique 模型仅支持整行更新，如果用户既需要唯一主键约束，又需要更新部分列（例如将多张源表导入到一张 doris 表的情形），则可以考虑使用 Aggregate 模型，同时将非主键列的聚合类型设置为 REPLACE_IF_NOT_NULL。具体的用法可以参考[语法手册](../sql-manual/sql-reference/Data-Definition-Statements/Create/CREATE-TABLE.md)
+2. Unique 模型针对需要唯一主键约束的场景，可以保证主键唯一性约束。但是无法利用 ROLLUP 等预聚合带来的查询优势。对于聚合查询有较高性能需求的用户，推荐使用自1.2版本加入的写时合并实现。
3. Duplicate 适合任意维度的 Ad-hoc 查询。虽然同样无法利用预聚合的特性，但是不受聚合模型的约束，可以发挥列存模型的优势（只读取相关列，而不需要读取所有 Key 列）。
+4. 如果有部分列更新的需求，请查阅文档[部分列更新](../data-operate/update-delete/partial-update.md)获取相关使用建议
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