Mathematical operators are provided for many PostgreSQL types. For types without standard mathematical conventions (e.g., date/time types) we describe the actual behavior in subsequent sections.
    Table 9.4 shows the mathematical
    operators that are available for the standard numeric types.
    Unless otherwise noted, operators shown as
    accepting numeric_type are available for all
    the types smallint, integer,
    bigint, numeric, real,
    and double precision.
    Operators shown as accepting integral_type
    are available for the types smallint, integer,
    and bigint.
    Except where noted, each form of an operator returns the same data type
    as its argument(s).  Calls involving multiple argument data types, such
    as integer + numeric,
    are resolved by using the type appearing later in these lists.
   
Table 9.4. Mathematical Operators
| Operator Description Example(s) | 
|---|
| 
         Addition 
         | 
| 
         Unary plus (no operation) 
         | 
| 
         Subtraction 
         | 
| 
         Negation 
         | 
| 
         Multiplication 
         | 
| 
         Division (for integral types, division truncates the result towards zero) 
         
         
         | 
| 
         
        Modulo (remainder); available for  
         | 
| 
         
         Exponentiation 
         
        Unlike typical mathematical practice, multiple uses of
         
         
         | 
| 
         Square root 
         | 
| 
         Cube root 
         | 
| 
         
        Factorial
        (deprecated, use  
         | 
| 
         
        Factorial as a prefix operator
        (deprecated, use  
         | 
| 
         Absolute value 
         | 
| 
         Bitwise AND 
         | 
| 
         Bitwise OR 
         | 
| 
         Bitwise exclusive OR 
         | 
| 
         Bitwise NOT 
         | 
| 
         Bitwise shift left 
         | 
| 
         Bitwise shift right 
         | 
   Table 9.5 shows the available
   mathematical functions.
   Many of these functions are provided in multiple forms with different
   argument types.
   Except where noted, any given form of a function returns the same
   data type as its argument(s); cross-type cases are resolved in the
   same way as explained above for operators.
   The functions working with double precision data are mostly
   implemented on top of the host system's C library; accuracy and behavior in
   boundary cases can therefore vary depending on the host system.
  
Table 9.5. Mathematical Functions
Table 9.6 shows functions for generating random numbers.
Table 9.6. Random Functions
   The random() function uses a simple linear
   congruential algorithm.  It is fast but not suitable for cryptographic
   applications; see the pgcrypto module for a more
   secure alternative.
   If setseed() is called, the series of results of
   subsequent random() calls in the current session
   can be repeated by re-issuing setseed() with the same
   argument.
   Without any prior setseed() call in the same
   session, the first random() call obtains a seed
   from a platform-dependent source of random bits.
  
Table 9.7 shows the available trigonometric functions. Each of these functions comes in two variants, one that measures angles in radians and one that measures angles in degrees.
Table 9.7. Trigonometric Functions
    Another way to work with angles measured in degrees is to use the unit
    transformation functions radians()degrees()sind(30).
   
Table 9.8 shows the available hyperbolic functions.
Table 9.8. Hyperbolic Functions