The general syntax rules for the DDL and the DCL in ABAP CDS are:
- Keywords
- Keywords must be all uppercase, all lowercase, or in lowercase with an uppercase initial letter. Mixed uppercase and lowercase is not allowed.
- Names
- Names are not case-sensitive.
- A name can have a maximum of 30 characters.
- A name can consist of letters, numbers, underscores (_), and slashes (/).
- A name must start with a letter or a forward slash character.
- The following CDS keywords cannot be used in names: ALL, AND, AS, ASSOCIATION, AVG, CASE, CAST, COUNT, DISTINCT, EXISTS, EXTEND, FROM, FULL, GROUP, HAVING, INNER, JOIN, KEY, LEFT, MAX, MIN, NOT, NULL, ON, OR, ORDER, RIGHT, SELECT, SUM, UNION, VIEW, WHEN, WHERE
- Literals
- Numeric literals must always be specified in full and a decimal point (.) used as a decimal separator if necessary.
- Character literals are enclosed in single quotations marks (').
- Comments
- Two forward slashes (//) introduce a comment, which continues until the end of the line.
- Comments within lines or that span multiple lines are enclosed by the characters /* and */.
- Separators
- Statements can be closed using a semicolon (;). This is optional.
- Protected Words
- Certain keywords are protected and cannot be used as self-defined names.
Examples
- SELECT, select, and Select are valid ways are specifying a keyword. seLect and SeLect, on the other hand, produce syntax errors.
- MYVIEW, myview, and myView all identify the same operand.
- 0.5 is a valid numeric literal, but .5 is not.