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Table of Contents
- Search Condition
- Scope
- SQL Syntax
- Parameters
- Description
- BETWEEN Predicate
- Scope
- SQL Syntax
- Parameters
- Description
- Example
- Comparison Predicate
- Scope
- SQL Syntax
- Parameters
- Description
- Example
- EXISTS Predicate
- Scope
- SQL Syntax
- Parameters
- Description
- Example
- IN Predicate
- Scope
- SQL Syntax
- Parameters
- Description
- Example
- LIKE Predicate
- Scope
- SQL Syntax
- Parameters
- Description
- Example
- NULL Predicate
- Scope
- SQL Syntax
- Parameters
- Description
- Example
- Quantified Predicate
- Scope
- SQL Syntax
- Parameters
- Description
- Example
This chapter discusses search condition clauses and the predicates used in
them. The following sections are presented:
Search Condition
BETWEEN Predicate
Comparison Predicate
EXISTS Predicate
IN Predicate
LIKE Predicate
NULL Predicate
Quantified Predicate
A search condition specifies criteria for choosing rows to select, update,
delete, insert, permit in a table, or fire rules on. Search conditions are
parameters in the following statements:
In the SELECT statement, search conditions are used for two
purposes as follows:
In the WHERE clause, to determine rows to retrieve for further
processing. The only expressions not valid in this clause are
aggregate functions and expressions containing LONG columns that
are not in long column functions.
In the HAVING clause, to specify a test to apply to each group
of rows surviving the GROUP BY clause test(s). If a GROUP BY
clause is not used, the test is applied to all the rows meeting
the WHERE clause conditions. References in a HAVING clause to
non-grouping columns must be from within aggregate functions.
Grouping columns can be referred to by name or with an aggregate
function.
In the UPDATE statement, search conditions in the WHERE
clause identify rows that qualify for updating.
In the DELETE statement, search conditions in the WHERE
clause identify rows that qualify for deletion.
In the INSERT statement, search conditions in the embedded
SELECT statement identify rows to copy from one or more tables
or views into a table.
In the DECLARE CURSOR statement, search conditions in the
embedded SELECT statement identify rows and columns to be
processed with a cursor.
In the CREATE VIEW statement, search conditions in the
embedded SELECT statement identify rows and columns that
qualify for the view.
In table CHECK constraints, the search condition
identifies valid rows that a table may contain.
In rule firing conditions, search conditions identify conditions
that cause rules to fire.
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