FLOOR¶

Syntax¶

FLOOR( <input_expr> [, <scale_expr> ] )

Arguments¶

input_expr

The value or expression to operate on. The data type should be one of the numeric data types, such as FLOAT or NUMBER.

scale_expr

The number of digits the output should include after the decimal point. The expression should evaluate to an integer from -38 to +38.

The default scale_expr is zero, meaning that the function removes all digits after the decimal point.

For information about negative scales, see the Usage Notes below.

Returns¶

The return type is based on the input type:

• If the input expression is a FLOAT, the returned type is a FLOAT.

• If the input expression is a NUMBER, the returned type is a NUMBER.

  • If the input scale is constant:

    • If the input scale is positive, the returned type has a scale equal to the input scale and has a precision large enough to encompass any possible result.

    • If the input scale is negative, the returned type has a scale of 0.

  • If the input scale is not constant, the returned type’s scale is the same as the input expression’s.

If the scale is zero, then the value is effectively an INTEGER.

For example:

• The data type returned by FLOOR(3.14::FLOAT, 1) is FLOAT.

• The NUMBER returned by FLOOR(3.14, 1) has scale 1 and precision at least 3.

• The NUMBER returned by FLOOR(-9.99, 0) has scale 0 and precision at least 2.

• The NUMBER returned by FLOOR(33.33, -1) has scale 0 and precision at least 3.

Usage notes¶

• If scale_expr is negative, then it specifies the number of places before the decimal point to which to adjust the number. For example, if the scale is -2, then the result is a multiple of 100.

• If scale_expr is larger than the input expression scale, the function does not have any effect.

• If either the input_expr or the scale_expr is NULL, then the result is NULL.

• When negative numbers are rounded down, the value is further from 0. For example, FLOOR(-1.1) is -2, not -1.

• If rounding the number downward brings the number outside of the range of values of the data type, an error is returned.

Examples¶

This example demonstrates the function without the scale_expr parameter:

SELECT FLOOR(135.135), FLOOR(-975.975);
+----------------+-----------------+
| FLOOR(135.135) | FLOOR(-975.975) |
|----------------+-----------------|
|            135 |            -976 |
+----------------+-----------------+

Copy

This example demonstrates the function with the scale_expr parameter, including with the scale set to negative numbers:

Create and fill a table:

CREATE TABLE test_floor (n FLOAT, scale INTEGER);
INSERT INTO test_floor (n, scale) VALUES
   (-975.975, -1),
   (-975.975,  0),
   (-975.975,  2),
   ( 135.135, -2),
   ( 135.135,  0),
   ( 135.135,  1),
   ( 135.135,  3),
   ( 135.135, 50),
   ( 135.135, NULL)
   ;

Copy

Output:

SELECT n, scale, FLOOR(n, scale)
  FROM test_floor
  ORDER BY n, scale;
+----------+-------+-----------------+
|        N | SCALE | FLOOR(N, SCALE) |
|----------+-------+-----------------|
| -975.975 |    -1 |        -980     |
| -975.975 |     0 |        -976     |
| -975.975 |     2 |        -975.98  |
|  135.135 |    -2 |         100     |
|  135.135 |     0 |         135     |
|  135.135 |     1 |         135.1   |
|  135.135 |     3 |         135.135 |
|  135.135 |    50 |         135.135 |
|  135.135 |  NULL |            NULL |
+----------+-------+-----------------+

Copy