1. Computer Science & Engineering 2111 CSE 2111 Lecture Querying a Database 1CSE 2111 Lecture- Querying a Database

2. What is a Database Query? 2 A request for information from a database To extract information from the Database you must use a Query which is a “question” or “request” – Criterion An expression that tells the DBMS which records to retrieve Make up of conditions – Can be one conditions or many When you run the query a dynaset, or subset of the database is displayed. You can make changes to this dynaset and the changes will be reflected in your database, because the dynaset is just a view of your database. CSE 2111 Lecture- Querying a Database

3. 3 Query By Example (QBE) Grid CSE 2111 Lecture- Querying a Database Dynaset created when Query is run

4. SQL is the language you use to talk to the database MS Access 2010 supplies a graphical user interface (GUI) called the Query By Example Grid or (QBE) grid MS Access 2010 creates the SQL for you. 4 Structured Query Language (SQL) CSE 2111 Lecture- Querying a Database

5. 5 SQL Created from QBE Grid CSE 2111 Lecture- Querying a Database