ABAP CDS

The following sections summarize the language elements of the DDL and DCL of the ABAP CDS, arranged by topics. 
•DDL
◦CDS Views
◦CDS View Enhancements
•DCL
◦CDS Roles
◦CDS Access Policies

In addition to the language elements show here, CDS source code can also contain annotations for metadata. 
 
 DDL 
 
 CDS Views 

 Keywords and Additions 

Language Element Meaning 
DEFINE VIEW ... AS Defines a CDS view 
WITH PARAMETERS Defines input parameters of a CDS view 
SELECT [DISTINCT] ... FROM SELECT statement of a CDS view 
INNER JOIN ... ON Inner join in a SELECT statement 
LEFT|RIGHT OUTER JOIN ... ON Outer join in a SELECT statement 
ASSOCIATION ... TO ... AS ... ON Defines an association for a path expression in a SELECT statement 
1: Attribute of a path expression 
INNER ... WHERE Attribute of a path expression 
LEFT OUTER ... WHERE Attribute of a path expression 
KEY ... AS Element of a SELECT list 
$EXTENSION.* Elements of an enhancement in a SELECT list 
WHERE ... WHERE clause of a SELECT statement 
GROUP BY ... GROUP-BY clause of a SELECT statement 
HAVING ... HAVING clause of a SELECT statement 
UNION ALL ... UNION clause of a SELECT statement 


 Expressions 

Operators Meaning 
MAX, MIN, AVG, SUM, COUNT Aggregate expressions in a SELECT statement 
+, -, *, / Arithmetic expressions in a SELECT statement 
CASE, WHEN, THEN, ELSE, END Case distinctions in a SELECT statement 
CAST Casting expression in a SELECT statement 
=, <>, <, >, <=, >=, BETWEEN, LIKE, IS NULL, NOT, AND, OR Relational expressions in a SELECT statement 


 Predefined Functions 

Function Meaning 
ABS, CEIL, DIV, DIVISION, FLOOR, MOD, ROUND Numeric functions in a SELECT statement 
CONCAT, LPAD, REPLACE, SUBSTRING String functions in a SELECT statement 
COALESCE Coalesce function in a SELECT statement 
CURRENCY_CONVERSION, UNIT_CONVERSION, DECIMAL_SHIFT Conversion functions in a SELECT statement 

 
 CDS View Enhancements 

 Keywords and Additions 

Language Element Meaning 
EXTEND VIEW ... WITH Enhancement of a CDS view with an CDS view enhancement 

 
 DCL 
 
 CDS Roles 

 Keywords and Additions 

Language Element Meaning 
DEFINE ROLE ... GRANT SELECT ON Defines a CDS role 
WHERE, AND, OR WHERE clause in the definition of a CDS role 
... = ASPECT pfcg_auth ... Condition for mapping roles 
... =|<>|<|>|<=|>=|LIKE|IS NULL ASPECT ... Condition for assignment roles 
... =|<>|<|>|<=|>=|LIKE|IS NULL ... Literal condition 

 
 CDS Access Policies 

 Keywords and Additions 

Language Element Meaning 
DEFINE ACCESSPOLICY Defines a CDS access policy 
DEFINE ASPECT ... AS Defines a CDS aspect 
SELECT FROM SELECT statement of an CDS aspect 
WHERE $user IN WHERE clause of the SELECT statement of an CDS aspect 
原文地址:https://www.cnblogs.com/JackeyLove/p/13495781.html