Numeric Data Types

Numeric data types are numbers stored in database columns. These data types are typically grouped by:

• Exact numeric types, values where the precision and scale need to be preserved. The exact numeric types are INTEGER, BIGINT, DECIMAL, NUMERIC, NUMBER, and MONEY.
• Approximate numeric types, values where the precision needs to be preserved and the scale can be floating. The approximate numeric types are DOUBLE PRECISION, FLOAT, and REAL.

Implicit casts from INTEGER, FLOAT, and NUMERIC to VARCHAR are not supported. If you need that functionality, write an explicit cast using one of the following forms:

CAST(numeric-expression AS data-type)

numeric-expression::data-type

For example, you can cast a float to an integer as follows:

=> SELECT(FLOAT '123.5')::INT; 
 ?column?
----------
      124
(1 row)

String-to-numeric data type conversions accept formats of quoted constants for scientific notation, binary scaling, hexadecimal, and combinations of numeric-type literals:

• Scientific notation:

  => SELECT FLOAT '1e10';  
    ?column?
  -------------
   10000000000
  (1 row)
  

• BINARY scaling:

  => SELECT NUMERIC '1p10'; 
   ?column?
  ----------
       1024
  (1 row)
  

• hexadecimal:

  => SELECT NUMERIC '0x0abc'; 
   ?column?
  ----------
       2748
  (1 row)