Egenskaper för sammanslagning

Om du dubbelklickar på en anslutning mellan två länkade fält i sökningsutkastet, eller om du väljer Infoga - Ny relation visas dialogrutan Egenskaper för sammanslagning. Dessa egenskaper kommer att användas i alla sökningar som skapas i framtiden.

Så här använder du det här kommandot...

Öppna sökningsutkast och välj Infoga - Ny relation, eller dubbelklicka på en förbindelselinje mellan två tabeller.

Inkluderade tabeller

Anger två olika tabeller som du vill relatera.

Inkluderade fält

Anger två datafält som ska kopplas samman med en relation.

Alternativ

Typ

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

Inre

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.

Vänster

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.

Höger

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.

Fullständig

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.

Natural

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.