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# 連結特性

若在查詢設計中連按兩下連結兩個欄位的連線，或選擇 [插入] - [新關係]，則螢幕上會顯示 [連結特性] 對話方塊。這些特性可用於以後建立的所有查詢中。

若要使用此指令...

Open query design and choose Insert - New Relation, or double-click on a connection line between two tables.

## 使用的表格

指定要連結的兩個不同的表格。

## 使用的欄位

指定兩個將以關係連結的資料欄位。

## 選項

### 類型

Specifies the join type of the selected join. Some databases support only a subset of the various possible types.

### 內部連結

In an inner join, the results table contains only those records for which the content of the linked fields is the same. In LibreOffice SQL this type of link is created by a corresponding WHERE clause.

### 左連結

In a left join, the results table contains all records of the queried fields from the left table and only those records of the queried fields from the right table for which the content of the linked fields is the same. In LibreOffice SQL this type of link corresponds to the LEFT OUTER JOIN command.

### 右連結

In a right join, the results table contains all records of the queried fields from the right table and only those records of the queried fields from the left table for which the content of the linked fields is the same. In LibreOffice SQL this type of link corresponds to the RIGHT OUTER JOIN command.

### 完整連結

In a full join, the results table contains all records of the queried fields from the left and right tables. In the SQL of LibreOffice this type of link corresponds to the FULL OUTER JOIN command.

### 自然

In a natural join, the keyword NATURAL in inserted into the SQL statement that defines the relation. The relation joins all columns that have the same column name in both tables. The resulting joined table contains only one column for each pair of equally named columns.