Read this SQL tutorial to learn when to use SELECT, JOIN, subselects and UNION to access multiple tables with a single statement. It’s sometimes difficult to know which SQL syntax to use when ...

The INNER JOINS: Matching records only In December 2001’s “Another crash course in SQL,” I showed you one way to extract information from two tables in one statement. In most implementations ...

Shold both fields be unique? -- country_name VARCHAR(40) NOT NULL UNIQUE, /* 14. Write a SQL statement to create a table job_history including columns employee_id, start_date, end_date, job_id and ...

Dropping an index in SQL is a common task for database developers, especially when they need to optimize the performance, storage, or maintenance of their tables. However, dropping an index also ...

Analyze database contents using basic, intermediate and advanced SQL statement syntax and usage. Demonstrate capability to query data from multiple tables using SQL JOINS. Create and modify database ...

SQL*Plus prompts you for your password. Type the password and press "Enter" again. Enter the Oracle "ALTER INDEX" command, using the following code as an example:ALTER INDEX table_index_ix REBUILD ...

See Updating PROC SQL and SAS/ACCESS Views ... To add, drop, or modify a column's definition or attributes, use the ALTER TABLE statement, described in ALTER TABLE Statement. In the SET clause, a ...