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7 Developing Procedures
SQL in SAP HANA includes extensions for creating procedures, which enables you to embed data-intensive
application logic into the database, where it can be optimized for performance (since there are no large data
transfers to the application and features such as parallel execution is possible). Procedures are used when other
modeling objects, such as analytic or attribute views, are not sufficient.
Some of the reasons to use procedures instead of standard SQL:
● SQL is not designed for complex calculations, such as for financials.
● SQL does not provide for imperative logic.
● Complex SQL statements can be hard to understand and maintain.
● SQL queries return one result set. Procedures can return multiple result sets.
● Procedures can have local variables, eliminating the need to explicitly create temporary tables for
intermediate results.
Procedures can be written in the following languages:
● SQLScript: The language that SAP HANA provides for writing procedures.
● R: An open-source programming language for statistical computing and graphics, which can be installed and
integrated with SAP HANA.
There are additional libraries of procedures, called Business Function Library and Predictive Analysis Library, that
can be called via SQL or from within another procedure.
SQL Extensions for Procedures
SQL includes the following statements for enabling procedures:
● CREATE TYPE: Creates a table types, which are used to define parameters for a procedure that represent
tabular results. For example:
CREATE TYPE tt_publishers AS TABLE (
publisher INTEGER,
name VARCHAR(50),
price DECIMAL,
cnt INTEGER);
● CREATE PROCEDURE: Creates a procedure. The LANGUAGE clause specifies the language you are using to
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code the procedure. For example:
CREATE PROCEDURE ProcWithResultView(IN id INT, OUT o1 CUSTOMER)
LANGUAGE SQLSCRIPT READS SQL DATA WITH RESULT VIEW ProcView AS
BEGIN
o1 = SELECT * FROM CUSTOMER WHERE CUST_ID = :id;
END;
P U B L I C
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SAP HANA Developer Guide
Developing Procedures