If both endpoints of the line attach to the same table, the relationship is a reflexive relationship. For a one-to-many relationship, the foreign-key table is the table near the line's figure-eight symbol. Related Tables The relationship line indicates that a foreign-key relationship exists between one table and another. If the line appears dotted, the DBMS does not enforce referential integrity for the relationship when rows are added or modified in the foreign-key table. If the line appears solid, the DBMS enforces referential integrity for the relationship when rows are added or modified in the foreign-key table. Line Style The line itself (not its endpoints) indicates whether the Database Management System (DBMS) enforces referential integrity for the relationship when new data is added to the foreign-key table. If a relationship has a key at each endpoint, it is a one-to-one relationship. If a relationship has a key at one endpoint and a figure-eight at the other, it is a one-to-many relationship. Within a database diagram, each relationship can appear with three distinct features: endpoints, a line style, and related tables.Įndpoints The endpoints of the line indicate whether the relationship is one-to-one or one-to-many. You can view a table in any of five different views to help you manage the size and layout of your diagram.įor more information about table views, see Customize the Amount of Information Displayed in Diagrams (Visual Database Tools). Property Columns The set of property columns is visible only in the certain views of your table. For information about primary keys, see Working with Keys. The row selector displays a key symbol if the column is in the table's primary key. Row Selector You can click the row selector to select a database column in the table.
For information about saving modified tables and diagrams, see Work with Database Diagrams (Visual Database Tools) If you have modified a table and have not yet saved it, an asterisk (*) appears at the end of the table name to indicate unsaved changes. Title Bar The title bar shows the name of the table Within a database diagram, each table can appear with three distinct features: a title bar, a row selector, and a set of property columns.
For example, you can create a large diagram showing all tables and columns, and you can create a smaller diagram showing all tables without showing the columns.Įach database diagram you create is stored in the associated database. Thus, you can create different diagrams to visualize different portions of the database, or to accentuate different aspects of the design. To visualize a database, you can create one or more diagrams illustrating some or all of the tables, columns, keys, and relationships in it.įor any database, you can create as many database diagrams as you like each database table can appear on any number of diagrams. When designing a database, you can use Database Designer to create, edit, or delete tables, columns, keys, indexes, relationships, and constraints.
The Database Designer is a visual tool that allows you to design and visualize a database to which you are connected. Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Analytics Platform System (PDW)
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