Maintenance Modifying the data –Add records –Delete records –Update records Modifying the design –Add fields into tables –Remove fields from a table –Change characteristics of existing fields

Query Types Select Query – chooses data from a table and displays it. Update Query – updates records in a table Delete Query – deletes records from a table.

Validation Rules Validation Rules are rules that a user must follow when entering data into a database. Validation Text – the message that appears if the user enters the wrong type of data.

Validation Rules Indicate that a field is required Entry must lie within a given range Specify a valid collection of values Specify a default value Change lowercase to UPPERCASE

Referential Integrity Primary Key - unique identifier for each record in a table. Foreign Key – a field in a table whose values must match a primary key in another table.

Referential Integrity We can define a relationship between two tables. ONE – to – MANY Relationship Primary key Foreign Key