SQL Sequence First and Last Functions

The seq_first_int() and seq_last_int() functions return the first or last element values in a sequence of integers; likewise seq_first_real(), and seq_last_real() return the first and last values for a sequence of real values.

Note that seq_first_int() and seq_last_int()require an integer sequence in input and return the first and last integer value in the sequence. Likewise seq_first_real() and seq_last_real() require a sequence of real values in input and return the first and last real value.

Following is an example script demonstrating the seq_first_int(), seq_last_int(), seq_first_real() and seq_last_real() functions:

 
 
    INSERT INTO SimpleSequence(testNumber,iVal1,fVal1)
    VALUES(2,'{-3,-2,-1,0,1,2,3}','{11.1,17.7,-23.3,42.5}');
     
    SELECT seq_first_int(iVal1) AS "first_int", seq_last_int(iVal1) AS "last_int",
        seq_first_real(fVal1) AS "first_real", seq_last_real(fVal1) AS "last_real"
    FROM SimpleSequence WHERE testNumber = 2;
     
    first_int   last_int   first_real      last_real
    ---------------------------------------------------------
    -3      	    3          11.100000       42.500000
     

Sample script

A sample script to demonstrate this select statement using xSQL can be run from the samples/xsql/scripts/financial directory with the following command:

     
    f 1