This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Join Equijoin Syntax Select table1.column, table1.column, table2.column From table1, table2 Where table1.column1=table2.column2 Table.column is a table name and a column name from which the data are retrieved. table1.column1=table2.column2 is a condition that joins or relates the tables together. Guidelines- When writing a SELECT statement that joins tables, precede the column name with the table name for clarity and to avoid ambiguity.- If the same column name appears in more than one table, then column name must be preceded with a table name.- To join tables together, you need a minimum of the number of join conditions as the number of tables minus one. For instance, to join 4 tables, you would need at least 3 joins. Use employees table you created for the aggregation exercise. Create departments table, and change the employees table to make departmentid a...
View Full Document
This note was uploaded on 12/22/2009 for the course DBST DBST 651 taught by Professor Yelena - ta during the Spring '09 term at MD University College.
- Spring '09
- Yelena - TA