Do review your SQL query program before put it into application program with these ideas. Read more.
Multiple nested query and Correlated sub-query both are different. Try to understand these with examples Multiple nested query-A subquery can contain another query, making it
SQL query use for both INSERT into values and SELECT to save time.
SQL round and truncate decimal functions used in banking project.
Index is popular object in DB2 SQL. Popular questions to your instant knowledge given for quick reference.
Resolution to solve SQL ambiguous column quickly useful to all SQL developers.
Sub queries you can give at four places in main query. Those are SELECT, WHERE, HAVING and in FROM clause. To understand these examples clearly you must listen few tips here.
Sub queries are like queries with in the query. You can write subquery such that it will return single value or multiple values. Read more example and explanation.