The keywords INNER and OUTER specify the join type. Syntax options for joining tables include: The exact syntax depends on the database you are using and on how you have defined the join. This situation occurs most often when you have created a join manually.Ī join can be expressed in a number of ways in an SQL statement. Query and View Designer cannot determine the join type. The following table lists the types of joins and the icons displayed on the ends of the join line. The symbols on the ends of the join line indicate the type of join. Outer join in which all rows from the table represented on the right will be included, even if they do not have matches in the related table.įull outer join in which all rows from both tables will be included, even if they do not have matches in the related table. Outer join in which all rows from the table represented on the left will be included, even if they do not have matches in the related table. ![]() Inner join based on the "greater than" operator. Inner join (created using an equal sign). The following table lists the icons that appear in the join line. If the join clause uses an operator other than equal (=), the operator appears in the join line icon. The shape of the icon in the middle of the join line indicates how the tables or table-structured objects are joined. If the joined data columns are not displayed (for example, the rectangle representing the table or table-structured object is minimized or the join involves an expression), the Query and View Designer places the join line at the title bar of the rectangle representing the table or table-structured object. If tables are joined using more than one join condition, the Query and View Designer displays multiple join lines, as in the following example: For example, the following illustration shows a join line between two tables that are joined: ![]() The Query and View Designer displays one join line for each join condition. ![]() In the Diagram pane the Query and View Designer displays a join line between the data columns involved in the join. If tables are joined, the Query and View Designer represents the join graphically in the Diagram pane and by using SQL syntax in the SQL pane.
0 Comments
Leave a Reply. |