Conditional functions
Functions that return a conditional result.
coalesce
Returns the first non-null argument, if any, otherwise null.
Syntax
coalesce(expression, …)
Parameters
Parameter
Type
Description
Required
expression
array, boolean, double, duration, ip, long, record, string, timeframe, timestamp
Returned if previous arguments are null.
required
Returns
Returns the first non-null argument, if any, otherwise null.
Examples
Example 1
data record(a = "a", b = "b", c = "c"),record(b = "b", c = "c"),record(c = "c"),record()| fieldsAdd coalesce(a, b, c)
Query result:
a
b
c
coalesce(a, b, c)
a
b
c
a
null
b
c
b
null
null
c
c
null
null
null
null
if
Evaluates the condition, and returns the value of either the then or else parameter.
Syntax
if(condition, then [, else])
Parameters
Parameter
Type
Description
Required
condition
boolean
The condition to check.
required
then
array, boolean, double, duration, ip, long, record, string, timeframe, timestamp
The expression if the condition is true.
required
else
array, boolean, double, duration, ip, long, record, string, timeframe, timestamp
The expression if the condition is false or null.
optional
Returns
Returns the value of the then parameter if the condition evaluated to true. Returns the value of the else parameter if the condition evaluated to false or null. Returns null if the condition evaluated to false or null and the else parameter is missing.
Examples
Example 1
data record(a = 10),record(a = 20)| fieldsAdd if(a < 15, "a is smaller than 15"),if(a < 15, "a is smaller than 15", else: "a is not smaller than 15")
Query result:
a
if(a < 15, "a is smaller than 15")
if(a < 15, "a is smaller than 15", else:"a is not smaller than 15")
10
a is smaller than 15
a is smaller than 15
20
null
a is not smaller than 15