chapter 5.3 Flashcards
1
Q
what are the 2 conditional expressions
A
case and decode
2
Q
which conditional expression is similar to case
A
NULLIF
3
Q
what kind of statement is case
A
ANSI/ISO 99 SQL 99 compliant statement
4
Q
what kind of statement is decode
A
Oracle proprietary statement
5
Q
what is the rule for data types in the case, when and else expressions
A
data types must be the same
6
Q
syntax for case expression
A
CASE expr WHEN comparison_expr1 THEN return_expr1
ELSE else_expr
END
7
Q
what does decode do
A
compares an expression to each of the search values
8
Q
what is the syntax for decode
A
DECODE(column1|expression, search1, result 1
[, default1])
if the default is ommited null value is returned when search value doesnt match any of the value s
