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Advanced SQL AdvSQL Advanced SQL Sources: [Mel02] Melton & Simon: SQL:1999 Understanding Relational Language Components, 2002 [Con02] Connolly & Begg: Database Systems, 3rd ed, 2002 [Gul99] Gulutzan & Pelzer: SQL-99 Complete, Really, 1999 [Cel99] Joe Celko: SQL for Smarties, 2nd ed, 1999 Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Standards, Specs, Implementations, .. See [Con02] • SQL Standards chapter 5 – ANSI X3.135-1986, X3.168-1989 (ESQL), X3.135-1989 (IEF) – ISO/IEC 9075:1992 (SQL-92), 9075:1999 (SQL:1999), 9075:2003 (SQL:2003), 9075:2006 (SQL:2006), .. – FIPS PUB 127-2 (see http://www.ocelot.ca/) • Specifications – IBM SAA / SQL – X/Open • Implementations (dialects) – Vendors: IBM, Oracle, .. • Related standards – ISO IRDS – ISO RDA – X/Open XA Haaga-Helia, Martti Laiho 1997-2007 AdvSQL SQL:1999 Parts and Conformances (SQL:2003) [Gul99] • Part 1: SQL/Framework - fundamental concepts • Part 2: SQL/Foundation - syntax and operations • Part 3: SQL/Call-Level Interface - function library • Part 4: SQL/Persistent Stored Modules • Part 5: SQL/Host Language Bindings - ESQL – Ada, C, Cobol, Fortran, Mumps, Pascal, PL/I – (note: not included in SQL:2003) • Minimal Conformance – Core SQL Support • Enhanced Conformance – SQL Packages – SQL Flagger Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Parts of SQL:2003 • 9075-1 SQL/Framework • 9075-2 SQL/Foundation • 9075-3 SQL/CLI • 9075-4 SQL/PSM • 9075-9 SQL/MED • 9075-10 SQL/OLB • 9075-11 SQL/Schemata • 9075-13 SQL/JRT • 9075-14 SQL/XML Haaga-Helia, Martti Laiho 1997-2007 AdvSQL SQL:1999 Packages [Gul99] [Mel02] • Enhanced datetime facility package • Enhanced integrity management package • OLAP facilities package • PSM package • CLI package (call-level interface) • Basic object support package • Enhanced object support package • Active database package • SQL/MM package (multimedia) Haaga-Helia, Martti Laiho 1997-2007 AdvSQL SQL Flagger [Gul99] Flags non-conforming extensions • Core SQL Flagging • Part SQL Flagging • Package SQL Flagging • Syntax Only • Catalog Lookup - syntax and access violations – INFORMATION_SCHEMA (Compare with FIPS-127 flagger) Haaga-Helia, Martti Laiho 1997-2007 AdvSQL SQL Statement Classes [Gul99] • SQL-Schema statements (DDL) – CREATE / ALTER / DROP ... • SQL-data statements (~ DML) – INSERT, UPDATE, DELETE, SELECT, cursor management • SQL-transaction statements – START TRANSACTION, SET TRANSACTION, COMMIT, ... • SQL-control statements – CALL, RETURN • SQL-connection statements – CONNECT, SET CONNECTION, DISCONNECT • SQL-session statements – SET TIME ZONE, SET ROLE, SET SESSION ... • SQL-diagnostics statements – GET DIAGNOSTICS Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Terminology & Concepts ISO SQL-92, SQL:1999: • SQL Environment • SQL Objects • Schema objects hierarchy: [ [catalog.]schema .]object • Connection objects, Session objects • SQL Datatypes • SQL Language Implementation concepts only: • Database, Indexes, ... Haaga-Helia, Martti Laiho 1997-2007 AdvSQL SQL Object name classes • Cluster • Character Set • <AuthorizationID> • Collation • Privilige • Translation • Catalog • Trigger • Schema • Module • Table • SQL-invoked routine • View – procedure • Column – function • Domain and UDT • Constraint and Assertion Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Name class hierarchy (draft) Physical Server DB Instance (Database) Catalog AuthorizationID Schema Domain / UDT Table / View SQL-Routine Trigger Procedure Function Column Haaga-Helia, Martti Laiho 1997-2007 AdvSQL SQL-92 Definition Schema - just for defining the Information Schema views as part of the standard! Users Check_constraints Schemata Check_table_usage Data_Type_Descriptor Check_column_usage Domains Assertions Tables Table_privileges Views Column_privileges Columns Usage_privileges View_table_usage Character_sets View_column_usage Collations Table_constraints Translation Key_column_usage SQL_languages Referential_constraint Haaga-Helia, Martti Laiho 1997-2007 AdvSQL SQL-92 Information Schema - Implemetations should provide these DBMS independent views Applicable_Roles Check_constraints Schemata Assertions Data_Type_Privileges Table_privileges Domains Usage_privileges Tables Character_sets Views Collations Columns Translations View_table_usage SQL_Languages View_column_usage SQL_Features Table_constraints … Key_column_usage Referential_constraints Haaga-Helia, Martti Laiho 1997-2007 AdvSQL SQL Datatypes Pre-defined datatypes: Constructed datatypes: • Number types • reference types • Bit String types • locators • Binary String types • row types • Character String types • collection types • Temporal types (arrays) • Boolean types • User-defined types Haaga-Helia, Martti Laiho 1997-2007 AdvSQL … Data types See [Con02] chapter 6 • Boolean data – Boolean • Character data – Char[acter], Character Varying (Varchar), NChar, NVarchar,.. • Bit data – Bit, Bit varying (not included in SQL:2003) • Exact numeric data – Integer, Smallint, Numeric, Decimal • Approximate numeric data – Float, Real, Double precision • Temporal data – Datetime data: Date, Time, Timestamp .. [WITH TIME ZONE] – Interval Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Literals • Character 'some text' • National character [varying] N'ÅäöÆçÐĦ' 'ﻕﺥﺖﺁ'N • Integer 12345 • Smallint 12 • Numeric 1.234 123 • Decimal 1.234 • Float 1.23E3 1.23E-2 • Real 1.23E3 1.23E-2 • Bit [varying] B'01011111' (deleted in 2001) X'5F' Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Integrity Enhancement Feature (IEF) • Required data - Not Null • DOMAIN integrity • Entity integrity (EI) - Primary Key, Unique • Referential integrity (RI) - Foreign Key referential actions ON UPDATE / ON DELETE: – No Action – Cascade – Set NULL – Set Default • Enterprise constraints Assertions Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Create / Alter / Drop object DROP … [ RESTRICT | CASCADE ] CASCADE: Drops also the related objects RESTRICT: Drop command fails if related objects exist Note: implementations may differ Haaga-Helia, Martti Laiho 1997-2007 AdvSQL CREATE DOMAIN Syntax: CREATE DOMAIN <domain name> [AS] <data type> [ DEFAULT <default value> ] [ <domain constraint> ... ] [ COLLATE <collation name> ] <domain constraint> ::= [CONSTRAINT <constraint name> ] CHECK (<predicate> ) [ <constraint attributes> ] <constraint attributes> ::= NOT DEFERRABLE | DEFERRABLE [INITIALLY IMMEDIATE] Note: no implementations in mainstream products! Haaga-Helia, Martti Laiho 1997-2007 AdvSQL CREATE TABLE CREATE [ { GLOBAL | LOCAL} TEMPORARY] TABLE <table_name> ( <table element list> ) [ ON COMMIT {PRESERVE ROWS | DELETE ROWS} ] <table element> ::= <column definition> | < table constraint > | ... [Gul99] p 356 - Haaga-Helia, Martti Laiho 1997-2007 AdvSQL ALTER TABLE • ADD COLUMN ... • DROP COLUMN … [RESTRICT | CASCADE] • ALTER COLUMN .. SET DEFAULT .. • ALTER COLUMN .. DROP DEFAULT • ADD CONSTRAINT • DROP CONSTRAINT … [RESTRICT | CASCADE] See [Con02] 6.2 Haaga-Helia, Martti Laiho 1997-2007 AdvSQL CREATE VIEW [Con02] 6.4 [Gul99] p 376- • Syntax CREATE [RECURSIVE] VIEW <view_name> [ (column_name [, …] ) ] AS <query expression> [WITH [CASCADED | LOCAL] CHECK OPTION ] • Implementations: – View resolution, restrictions, updatablity – Macro: inline replacements – Materialized view into a hidden temporary base table Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Views Advantages Disadvantages • Data independence • Update restrictions • Currency • Structure restrictions – changes reflected immed. • Performance? • Improved Security • Reduced complexity • Convenience • Customization • Data integrity See [Con02] chapter 6.4.7 – With Check Option Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Materialized Views Advantages Disadvantages • Data independence • Update restrictions • Currency • Structure restrictions – changes reflected immed. • Performance? • Improved Security • Reduced complexity • Convenience • Customization • Data integrity See [Con02] chapter 6.4.7 – With Check Option Haaga-Helia, Martti Laiho 1997-2007 AdvSQL CREATE ASSERTION Syntax: CREATE ASSERTION <constraint name> CHECK (<predicate> ) [ <constraint attributes> ] Note: no implementations in mainstream products! Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Numeric Value Functions [Mel02] • ABS ( numeric-value ) • BIT_LENGTH ( string-value ) • OCTET_LENGTH ( string-value ) • CHAR_LEGTH ( character-string ) • CARDINALITY ( collection-value ) • POSITION ( string-value IN string-value ) • EXTRACT ( datetime-field FROM datetime-value ) • EXTRACT ( datetime-field FROM interval-value ) • EXTRACT ( timezone-field FROM datetime-value ) • MOD ( numeric-dividend , numeric-divisor ) Haaga-Helia, Martti Laiho 1997-2007 AdvSQL String Value Functions / Operators [Mel02] • SUBSTRING ( string-value FROM start [ FOR length ] ) • SUBSTRING ( string-value SIMILAR string-value ESCAPE character-value ) • UPPER ( character-string-value ) • LOWER ( character-string-value ) • TRIM ( [ BOTH | LEADING | TRAILING ] character FROM character-string-value ) • TRANSLATE ( character-string-value USING translation ) • CONVERT ( character-string-value USING conversion ) • OVERLAY (string-value PLACING string-value FROM start [ FOR length ] ) • string-value || string-value Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Built-in Scalar Operators/functions • USER • CURRENT_USER • SESSION_USER • SYSTEM_USER • CURRENT_ROLE • CURRENT_PATH Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Datetime Value Functions [Mel02] • CURRENT_DATE • CURRENT_TIME [ ( precision ) ] • CURRENT_TIMESTAMP [ ( precision ) ] • LOCALTIME [ ( precision ) ] • LOCALTIMESTAMP [ ( precision ) ] Haaga-Helia, Martti Laiho 1997-2007 AdvSQL Temporal
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