No-table SELECT

The no-table Select statement computes the constant expression, and the computing does not depend on tables and columns.

Syntax

NoTableSelectClause
	::= 'SELECT' SelectExprList
SelectExprList
         ::= SelectExpr ( ',' SelectExpr )*
SelectExpr    ::= ( Identifier '.' ( Identifier '.' )? )? '*'
           | ( Expression | '{' Identifier Expression '}' ) ['AS' Identifier]
     

SQL Template

SELECT const_expr [, const_expr ...];

Description

SELECT Statement Elements	Offline Mode	Online Preview Mode	Online Request Mode	Note
No-table SELECT statement	✓	✓		The no-table SELECT statement computes the constant expression operation list, and the computation does not depend on tables or columns

Examples

SELECT constant literal

SELECT 1, 1L, 1.0f, 2.0, 'Hello';

SELECT constant expression

SELECT 1+1, 1L + 1L, 1.0f - 1.0f, 2.0*2.0, 'Hello' LIKE 'He%';

SELECT function expression

SELECT substr("hello world", 3, 6);