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What helps to create relationships between multiple tables?
Drag a field (typically the primary key) from one table to the common field (the foreign key) in the other table. To drag multiple fields, press the CTRL key, click each field, and then drag them. The Edit Relationships dialog box appears.
Can we use one trigger for multiple tables?
SQL Server allows multiple triggers on the table for the same event and there is no defined order of execution of these triggers. We can set the order of a trigger to either first or last using procedure sp_settriggerorder. There can be only one first or last trigger for each statement on a table.
How can I get data from multiple tables in SQL?
There are many ways to display data from more than one table. You can join tables or views by a common column. You can also merge data from two or more tables or views into a single column or create a subquery to retrieve data from several tables. You can use a SELECT statement to join columns in two or more tables.
How do I make multiple tables into one query?
To create a multi-table query:
- Select the Query Design command from the Create tab on the Ribbon.
- In the dialog box that appears, select each table you want to include in your query and click Add.
- After you have added all of the tables you want, click Close.
Why is it better to have multiple separate tables?
Basically a single table is good when data is one-to-one. When you have thousands of rows and columns of data, where the data is one-to-many, multiple tables are better to reduce duplicate data.
Can a trigger be associated to a view?
Triggers may be created on views, as well as ordinary tables, by specifying INSTEAD OF in the CREATE TRIGGER statement. If one or more ON INSERT, ON DELETE or ON UPDATE triggers are defined on a view, then it is not an error to execute an INSERT, DELETE or UPDATE statement on the view, respectively.
Can a table have multiple foreign keys?
A table may have multiple foreign keys, and each foreign key can have a different parent table. Each foreign key is enforced independently by the database system.