Purpose
Represent values in sign/magnitude form ranging from 2.226 x 10308 to 1.797 x 10308.
Syntax
 attributes
 Appropriate data type attributes, column storage attributes, or column constraint attributes.
ANSI Compliance
REAL and DOUBLE PRECISION are in the ANSI SQL:2011 standard. FLOAT is a Teradata synonym for REAL and DOUBLE PRECISION.
Floating Point Value Storage and Manipulation
Eight bytes are used to hold a floating point value.
Floating point values are stored and manipulated internally in IEEE floating point format. Floating point values are stored with the least significant byte first, with one bit for the mantissa sign, 11 bits for the exponent, and 52 bits for the mantissa. The mantissa sign is in the most significant bit position; the exponent sign is a part of the exponent field (excess1024 notation, in which (1024  exponent) = sign).
Negative numbers differ from positive numbers of the same magnitude only in the sign bit.
Teradata Database supports normalized, but not nonnormalized, client floating point values.
The range of IEEE floating point values may be wider than that supported by the client system. Therefore, values can be created and stored in Teradata Database that return error messages when converted for delivery to the client system.
External Representation of FLOAT/REAL/DOUBLE PRECISION
The following table lists the client representations for the Teradata FLOAT/REAL/DOUBLE PRECISION data type.
Determining the application definitions and client data types is the responsibility of the application programmer.
Client CPU Architecture  Client Representation 

IBM mainframe  Eight byte 64bit (double precision) floating point number, most significant byte first, with the attributes as follows:

UTS  Eight byte 64bit (double precision) floating point number, most significant byte first, with the attributes as follows:


Eight byte 64bit (double precision) floating point number, most significant byte first, with the attributes as follows:

Intel  Eight byte 64bit (double precision) floating point number, least significant byte first, with the attributes as follows:

Example: FLOAT Data Type
In the following table definition, column SalaryFactor is a FLOAT data type:
CREATE TABLE Salaries (Id CHAR(9) ,SalaryFactor FLOAT BETWEEN .1 AND 1E1 );
Related Topics
FOR information on …  SEE … 

potential problems associated with floating point values in comparisons and computations  Operations on Floating Point Values. 
rounding and FLOAT/REAL/DOUBLE PRECISION types  Rounding. 