TRUNC

Rounds a number to its integer representation towards 0.

Note

This function is overloaded. The function TRUNC can also modify the precision of DATE and DATETIME values.

Syntax

TRUNC( expr )

Arguments

Parameter	Description
`expr`	Numeric expression

Returns

Returns the same type as the argument supplied.

When using the TRUNC floating point number scalar function, real arguments are automatically cast to double precision.

Notes

If the input value is NULL, the result is NULL.

Examples

Rounding to the nearest integer

numbers=> SELECT TRUNC(x) FROM (VALUES (0.0001), (PI()), (-2.718281), (500.1234)) as t(x);
trunc
-----
  0.0
  3.0
 -2.0
500.0

TRUNC vs. ROUND 

numbers=> SELECT TRUNC(x), ROUND(x)
.      FROM (VALUES (0.0001), (-0.0001)
.           , (PI()), (-2.718281), (500.1234)) as t(x);
trunc | round
------+------
  0.0 |  -0.0
 -0.0 |  -0.0
  3.0 |   3.0
 -2.0 |  -3.0
500.0 | 500.0