Which three tasks can be performed using SQL functions built into Oracle Database? (Choose
three.)
A.
Combining more than two columns or expressions into a single column in the output
B.
Displaying a date in a nondefault format
C.
Substituting a character string in a text expression with a specified string
D.
Finding the number of characters in an expression
all are correct i believe
Option A is wrong…
we can combine two or more columns by using || symbol but there is no inbuilt SQL function .
‘concat’ function can be operated only on 2 variables or columns, while ‘concat’ operation can be
done for any number of variables or columns.
Why option A is wrong.You can combine two or more columns using nested CONCAT
concat(concat(string1,string2),string3))