[doris] branch master updated: [doc](unique key) add suggestion for replace_if_not_null (#11223)

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The following commit(s) were added to refs/heads/master by this push:
     new e7635e54ee [doc](unique key) add suggestion for replace_if_not_null (#11223)
e7635e54ee is described below

commit e7635e54eeeb6276e4b490f877aff3929db4190f
Author: zhannngchen <48...@users.noreply.github.com>
AuthorDate: Fri Jul 29 20:02:18 2022 +0800

    [doc](unique key) add suggestion for replace_if_not_null (#11223)
---
 docs/en/docs/data-table/data-model.md    | 1 +
 docs/zh-CN/docs/data-table/data-model.md | 1 +
 2 files changed, 2 insertions(+)

diff --git a/docs/en/docs/data-table/data-model.md b/docs/en/docs/data-table/data-model.md
index a9c9ec0e2a..c1f2084084 100644
--- a/docs/en/docs/data-table/data-model.md
+++ b/docs/en/docs/data-table/data-model.md
@@ -450,4 +450,5 @@ Because the data model was established when the table was built, and **could not
 
 1. Aggregate model can greatly reduce the amount of data scanned and the amount of query computation by pre-aggregation. It is very suitable for report query scenarios with fixed patterns. But this model is not very friendly for count (*) queries. At the same time, because the aggregation method on the Value column is fixed, semantic correctness should be considered in other types of aggregation queries.
 2. Uniq model guarantees the uniqueness of primary key for scenarios requiring unique primary key constraints. However, the query advantage brought by pre-aggregation such as ROLLUP cannot be exploited (because the essence is REPLACE, there is no such aggregation as SUM).
+   - \[Note\] The Unique model only supports the entire row update. If the user needs unique key with partial update (such as loading multiple source tables into one doris table), you can consider using the Aggregate model, setting the aggregate type of the non-primary key columns to REPLACE_IF_NOT_NULL. For detail, please refer to [CREATE TABLE Manual](../sql-manual/sql-reference/Data-Definition-Statements/Create/CREATE-TABLE.md)
 3. Duplicate is suitable for ad-hoc queries of any dimension. Although it is also impossible to take advantage of the pre-aggregation feature, it is not constrained by the aggregation model and can take advantage of the queue-store model (only reading related columns, but not all Key columns).
diff --git a/docs/zh-CN/docs/data-table/data-model.md b/docs/zh-CN/docs/data-table/data-model.md
index 4e3fc609cb..90f8df7b86 100644
--- a/docs/zh-CN/docs/data-table/data-model.md
+++ b/docs/zh-CN/docs/data-table/data-model.md
@@ -459,4 +459,5 @@ Duplicate 模型没有聚合模型的这个局限性。因为该模型不涉及
 
 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（因为本质是 REPLACE，没有 SUM 这种聚合方式）。
+   - 【注意】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)
 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）。


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