The CHOOSE function is also a logical operator, but it
behaves in a somewhat different manner. CHOOSE is similar to an index in an
array, assuming the array is a list of arguments. The syntax for the CHOOSE
function is as follows:
CHOOSE (index, val_1, val_2 [, val_n])
Index is a 1-based integer that acts as the index into the
list of values. The corresponding values are the list of values that will be
searched. The following script illustrates the use of the function:
See the example
SELECT CHOOSE (3, 'Lions', 'Tigers', 'Bears') Result
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See the output
If the specified index value has a numeric data type other
than integer, then the numeric value will be implicitly converted to integer
type. For example, 3.68 will be converted to 3. See the example.
If there are no items in the specified index, or index out
of range, then CHOOSE function will return NULL value. If we use index as 5 in
given example it will return Null value. See the example.
If we use string as index value it will throw error. See the
example
