percentlie_approx¶
This function is used to return the approximate percentile, which is applicable to a large amount of data. It sorts a specified column in ascending order, and then obtains the value closest to the pth percentile.
Syntax¶
percentile_approx (colname,DOUBLE p)
Parameters¶
Parameter | Mandatory | Type | Description |
|---|---|---|---|
colname | Yes | STRING | Name of the column to be sorted The elements in a column are of the DOUBLE type. If an element in a column is not of the DOUBLE type, the system will implicitly convert it to the DOUBLE type for calculation. |
p | Yes | DOUBLE | The value can be a float, integer, or string. The value ranges from 0 to 1. The value is a float. |
Return Values¶
The return value is of the DOUBLE or ARRAY type.
Note
If the column name does not exist, an error is reported.
If the value of p is NULL or outside the range of [0,1], an error is reported.
Example Code¶
Assume that the elements in the int_test column are 1, 2, 3, and 4 and they are of the INT type.
The value 3 is returned.
select percentile_approx(int_test,0.7) FROM int_test;
The value 3 is returned.
select percentile_approx(int_test,0.75) FROM int_test;
The value 2 is returned.
select percentile_approx(int_test,0.5) FROM int_test;
The value [1,2,2,3,4] is returned.
select percentile_approx (int_test,ARRAY(0.1,0.3,0.5,0.6,0.9)) FROM int_test;