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 Data Types and SubtypesData Definition (DDL) Statements 
Introducer Syntax for String Literals

If necessary, a string literal may be preceded by a character set name, itself prefixed with an underscore “_”.This is known as introducer syntax.Its purpose is to inform the engine about how to interpret and store the incoming string.

Example

INSERT INTO People
VALUES (_ISO8859_1 'Hans-Jörg Schäfer')

Number Literals

A number literal is any valid number in a supported notation:

  • In SQL, for numbers in the standard decimal notation, the decimal point is always represented by period character (‘.’, full-stop, dot);thousands are not separated.Inclusion of commas, blanks, etc. will cause errors.

  • Exponential notation is supported.For example, 0.0000234 can be expressed as 2.34e-5.However, while the literal 0.0000234 is a NUMERIC(18,7), the literal 2.34e-5 is a DOUBLE PRECISION.

  • Hexadecimal notation — see below.

The format of the literal decides the type (<d> for a decimal digit, <h> for a hexadecimal digit):

Format Type

<d>[<d> …​]

INTEGER, BIGINT, INT128 or DECFLOAT(34) (depends on if value fits in the type).DECFLOAT(34) is used for values that do not fit in INT128.

0{x|X} <h>[<h> …​]

INTEGER for 1-8 <h>, or BIGINT for 9-16 <h>, INT128 for 17-32 <h>

<d>[<d> …​] "." [<d> …​]

NUMERIC(18, n), NUMERIC(38, n) or DECFLOAT(34) where n depends on the number of digits after the decimal point, and precision on the total number of digits.

For backwards compatibility, some values of 19 digits are mapped to NUMERIC(18, n).DECFLOAT(34) is used when the unscaled value does not fit in INT128.

<d>[<d> …​]["." [<d> …​]] E <d>[<d> …​]

DOUBLE PRECISION or DECFLOAT(34), where DECFLOAT is used only if the number of digits is 20 or higher, or the absolute exponent is 309 or greater.