Asked by: Abdellah Dercksen
technology and computing databases

What is where clause in Oracle?

Last Updated: 26th April, 2020

The Oracle WHERE Clause is used to restrict the rows returned from a query. Unlike the Oracle SELECT and FROM statements, which are necessary for creating a valid SQL query, the Oracle WHERE clause is optional. A SQL query can function properly with or without the Oracle WHERE clause.

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Furthermore, what is where clause in SQL?

A WHERE clause in SQL specifies that a SQL Data Manipulation Language (DML) statement should only affect rows that meet specified criteria. In brief SQL WHERE clause is used to extract only those results from a SQL statement, such as: SELECT, INSERT, UPDATE, or DELETE statement.

Beside above, can case be used in where clause in Oracle? Oracle CASE expression allows you to add if-else logic to SQL statements without having to call a procedure. For example, you can use the CASE expression in statements such as SELECT , UPDATE , or DELETE , and in clauses like SELECT , WHERE , HAVING , and ORDDER BY .

Similarly, what is a clause in Oracle?

In Oracle, HAVING Clause is used with GROUP BY Clause to restrict the groups of returned rows where condition is TRUE.

What does a (+) sign mean in an Oracle SQL where clause?

Oracle outer join operator (+) allows you to perform outer joins on two or more tables. Quick Example: -- Select all rows from cities table even if there is no matching row in counties table SELECT cities.

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