Examples for validating dates in plsql
Quoted identifiers are seldom needed, but occasionally they can be useful.They can contain any sequence of printable characters including spaces but excluding double quotes.In the last example, the implicit decimal point shifted three places to the right.In this example, it shifts three places to the left: A character literal is an individual character enclosed by single quotes (apostrophes).You choose a character that is not present in the string, and then do not need to escape other single quotation marks inside the literal: DECLARE d1 DATE := DATE '1998-12-25'; t1 TIMESTAMP := TIMESTAMP '1997-10-22 '; t2 TIMESTAMP WITH TIME ZONE := TIMESTAMP '1997-01-31 .66 '; -- Three years and two months -- For greater precision, we would use the day-to-second interval i1 INTERVAL YEAR TO MONTH := INTERVAL '3-2' YEAR TO MONTH; -- Five days, four hours, three minutes, two and 1/100 seconds i2 INTERVAL DAY TO SECOND := INTERVAL '5 .01' DAY TO SECOND; The PL/SQL compiler ignores comments, but you should not.Adding comments to your program promotes readability and aids understanding.Generally, you use comments to describe the purpose and use of each code segment.PL/SQL supports two comment styles: single-line and multi-line.
This chapter contains these topics: PL/SQL keywords are not case-sensitive, so lower-case letters are equivalent to corresponding upper-case letters except within string and character literals.
Character literals include all the printable characters in the PL/SQL character set: letters, numerals, spaces, and special symbols.
Some examples follow: A character value can be represented by an identifier or explicitly written as a string literal, which is a sequence of zero or more characters enclosed by single quotes.
Thus, the following identifiers are valid: respectively.
For the properties of the datatypes, see "PL/SQL Number Types".