Slide 16.26: SQL3

Slide 16.25: Standardization
Slide 16.27: Value and object types
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SQL3

SQL3 includes the following essential features: (i) extensions of SQL2, (ii) value and object types, and (iii) subtables.

Extensions of SQL2

Monitoring integrity constraints by using triggers.
Improved security measures based on the Grant and Revoke commands.
Extended query possibilities by using recursion, additional predicates, extended join operations etc. For example, Find all the amendments of the technical report with the acronym ZZ122:
SELECT technical_report ( RECURSES amendment_to ) WHERE acronym_document = 'ZZ122';

A restricted possibility to define complex structured values by means of the ROW data type, which renders an attribute tuple-value.

CREATE TABLE person (
  name    VARCHAR(40),
  age     INT,
  address ROW ( street    VARCHAR(30),
                location  VARCHAR(20),
                telephone ROW ( areacode CHAR(5),
                                number   CHAR(7) )));

New, predefined data types, in particular
- Enumeration types: For example,
- Boolean values
- Collection types: Nested tables and varying arrays.
- Large objects (LOBs) for holding large storage objects such as binary (BLOBs), character (CLOBs), or binary files (BFILEs).

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Slide 16.25: Standardization
Slide 16.27: Value and object types
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