SQL Guide - Scalar Literals

Scalar Literals

Scalar literals are used to represent constant values in expressions and search conditions within an SQL command or query. With some data types, the literal has to be preceded by the appropriate keyword (such as INTERVAL in the expr-primary-interval expression). The entries in the table below indicate if a keyword is required.

The following types of literal are supported:

Type	Description
Bit String	Written either as sequence of 0s and 1s, or as a sequence of hexadecimal digits. Examples: B'1010110111' X'3CF8'
Boolean	Written as single bit value, either `TRUE` or `FALSE`.
DateTime	A date, time, or timestamp value. Written as a keyword followed by a string literal that defines the date, time, or timestamp value. The keyword differs depending on the expression. For information about, and examples that show, the required format, see: Expressions.expr-primary-datetime Expressions.expr-primary-odbc-datetime (this ODBC expression also has to be enclosed within braces { }) Expressions.expr-primary-opc-time (to define an OPC relative time)
Integer	Written as a signed or unsigned integer number. Examples: 0 65535 -50
Interval	A duration. Written as the INTERVAL keyword, followed by a string literal that defines the interval. For information about, and examples that show, the required format, see Expressions.expr-primary-interval.
Location	For use on systems that use Geo SCADA Expert's Geographical Location features. A geographical location. Written as the LOCATION keyword, followed by a string literal that defines the location. For information about, and examples that show, the required format, see Expressions.expr-primary-location.
Real	Written as a floating point number. Examples: 0.5 100.0 5.75E-4 -2.5E12
Region	For use on systems that use Geo SCADA Expert's Geographical Location features. A geographical region. Written as the REGION keyword, followed by a string literal that defines the region. For information about, and examples that show, the required format, see Expressions.expr-primary-region.
String	A sequence of characters enclosed within single straight quotation marks. A single straight quotation mark is itself represented by two immediately adjacent single straight quotation marks (this is known as 'escaping'). Examples: `''` (an empty string) 'Some Text' `'Don''t stop'` (notice that the apostrophe in the string is preceded by a single straight quotation mark)

All numeric values in SQL use the English decimal point (a dot).