![]() ![]() SELECT e2.sal FROM emp e2 WHERE e2.deptno = 100 ![]() "x ALL (zero rows)" evaluates to TRUE, so all rows are displayed."x = ALL (.)": The value must be greater than or equal to the biggest value in the list to evaluate to TRUE."x > ALL (.)": The value must be greater than the biggest value in the list to evaluate to TRUE."x != ALL (.)": The value must not match any values in the list to evaluate to TRUE."x = ALL (.)": The value must match all the values in the list to evaluate to TRUE.Transformed to equivalent statement without ANY.Īssuming subqueries don't return zero rows, the following statements can be made for both list and subquery versions: Transformed to equivalent statement using ANY. When the ALL condition is followed by a subquery, the optimizer performs a two-step transformation as shown below. WHERE sal > 2000 AND sal > 3000 AND sal > 4000 Transformed to equivalent statement without ALL. When the ALL condition is followed by a list, the optimizer expands the initial condition to all elements of the list and strings them together with AND operators, as shown below. It must be preceded by =, !=, >, = and followed by a list or subquery. The ALL comparison condition is used to compare a value to a list or subquery. ALL, ANY and SOME Comparison Conditions in SQL.This extra information is not a requirement for the exam, but goes some way to explaining why you rarely see people using the conditions. The article also includes information about the transformations the optimizer does when processing them. If you are planning to sit the Oracle Database SQL Expert (1Z0-047) exam you should be familiar with these conditions as they are used frequently in the questions.Īll you need to know for the exam is the usage and characteristics of these comparison conditions. It is quite possible you could work with Oracle databases for many years and never come across the ALL, ANY and SOME comparison conditions in SQL because there are alternatives to them that are used more regularly. Home » Articles » Misc » Here ALL, ANY and SOME Comparison Conditions in SQL ![]()
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