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Oracle® Database Application Developer’s Guide - Expression Filter 10g Release 1 (10.1) Part No. B10821-01 December 2003 Oracle Database Application Developer’s Guide - Expression Filter, 10g Release 1 (10.1) Part No. B10821-01 Copyright © 2003 Oracle Corporation. All rights reserved. Primary Author: Aravind Yalamanchi Contributors: William Beauregard, Dieter Gawlick, Helen Grembowicz, Deborah Owens, and Jagannathan Srinivasan The Programs (which include both the software and documentation) contain proprietary information of Oracle Corporation; they are provided under a license agreement containing restrictions on use and disclosure and are also protected by copyright, patent and other intellectual and industrial property laws. Reverse engineering, disassembly or decompilation of the Programs, except to the extent required to obtain interoperability with other independently created software or as specified by law, is prohibited. 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Other names may be trademarks of their respective owners. iii Contents List of ExamplesList of Figures Send Us Your Comments xi Preface xiii Audience xiii Documentation Accessibility xiii Related Documentation xiv Conventions xiv 1 Oracle Expression Filter Concepts 1.1 What Is Expression Filter? 1-1 1.1.1 Expression Filter Usage Scenarios 1-2 1.2 Introduction to Expressions 1-3 1.2.1 Defining Attribute Sets 1-5 1.2.2 Defining Expression Columns 1-7 1.2.3 Inserting, Updating, and Deleting Expressions 1-10 1.3 Applying the SQL EVALUATE Operator 1-10 1.4 Evaluation Semantics 1-13 1.5 Granting and Revoking Privileges 1-13 1.6 Error Messages 1-14 2 Indexing Expressions 2.1 Concepts of Indexing Expressions 2-1 iv 2.2 Indexable Predicates 2-2 2.3 Index Representation 2-2 2.4 Index Processing 2-4 2.5 Predicate Table Query 2-6 2.6 Index Creation and Tuning 2-6 2.7 Index Usage 2-10 2.8 Index Storage and Maintenance 2-10 3 Expressions with XPath Predicates 3.1 Using XPath Predicates in Expressions 3-1 3.2 Indexing XPath Predicates 3-3 3.2.1 Indexable XPath Predicates 3-3 3.2.2 Index Representation 3-4 3.2.3 Index Processing 3-5 3.2.4 Index Tuning for XPath Predicates 3-6 4 Expression Filter Internal Objects 4.1 Attribute Set Object Type 4-1 4.2 Expression Validation Trigger 4-2 4.3 Expression Filter Index Objects 4-2 4.4 Expression Filter System Triggers 4-2 5 Using Expression Filter with Utilities 5.1 Bulk Loading of Expression Data 5-1 5.2 Exporting and Importing Tables, Users, and Databases 5-3 5.2.1 Exporting and Importing Tables Containing Expression Columns 5-3 5.2.2 Exporting a User Owning Attribute Sets 5-4 5.2.3 Exporting a Database Containing Attribute Sets 5-4 6 SQL Operators and Statements EVALUATE 6-2 ALTER INDEX REBUILD 6-5 ALTER INDEX RENAME TO 6-7 v CREATE INDEX 6-8 DROP INDEX 6-12 7 Object Types EXF$ATTRIBUTE 7-2 EXF$ATTRIBUTE_LIST 7-3 EXF$INDEXOPER 7-4 EXF$TABLE_ALIAS 7-6 EXF$XPATH_TAG 7-7 EXF$XPATH_TAGS 7-9 8 Management Procedures Using the DBMS_EXPFIL Package ADD_ELEMENTARY_ATTRIBUTE Procedure 8-3 ADD_FUNCTIONS Procedure 8-5 ASSIGN_ATTRIBUTE_SET Procedure 8-7 BUILD_EXCEPTIONS_TABLE Procedure 8-9 CLEAR_EXPRSET_STATS Procedure 8-10 COPY_ATTRIBUTE_SET Procedure 8-11 CREATE_ATTRIBUTE_SET Procedure 8-12 DEFAULT_INDEX_PARAMETERS Procedure 8-14 DEFAULT_XPINDEX_PARAMETERS Procedure 8-16 DEFRAG_INDEX Procedure 8-19 DROP_ATTRIBUTE_SET Procedure 8-20 GET_EXPRSET_STATS Procedure 8-21 GRANT_PRIVILEGE Procedure 8-22 INDEX_PARAMETERS Procedure 8-24 REVOKE_PRIVILEGE Procedure 8-27 UNASSIGN_ATTRIBUTE_SET Procedure 8-29 VALIDATE_EXPRESSIONS Procedure 8-30 XPINDEX_PARAMETERS Procedure 8-32 vi 9 Expression Filter Views 9.1 USER_EXPFIL_ASET_FUNCTIONS View 9-2 9.2 USER_EXPFIL_ATTRIBUTES View 9-2 9.3 USER_EXPFIL_ATTRIBUTE_SETS View 9-3 9.4 USER_EXPFIL_DEF_INDEX_PARAMS View 9-3 9.5 USER_EXPFIL_EXPRESSION_SETS View 9-3 9.6 USER_EXPFIL_EXPRSET_STATS View 9-4 9.7 USER_EXPFIL_INDEX_PARAMS View 9-5 9.8 USER_EXPFIL_INDEXES View 9-6 9.9 USER_EXPFIL_PREDTAB_ATTRIBUTES View 9-6 9.10 USER_EXPFIL_PRIVILEGES View 9-7 A Managing Expressions Defined on One or More Database Tables B Application Examples C Installing Oracle Expression Filter Index vii List of Examples 1–1 Defining an Attribute Set From an Existing Object Type 1-5 1–2 Defining an Attribute Set Incrementally 1-6 1–3 Adding User-Defined Functions to an Attribute Set 1-7 1–4 Inserting an Expression into the Consumer Table 1-10 1–5 Inserting an Expression That References a User-Defined Function 1-10 viii List of Figures 1–1 Expression Datatype 1-9 2–1 Conceptual Predicate Table 2-3 3–1 Conceptual Predicate Table with XPath Predicates 3-5 ix List of Tables 6–1 Expression Filter Index Creation and Usage Statements 6-1 8–1 DBMS_EXPFIL Procedures 8-1 9–1 Expression Filter Views 9-1 x [...]... Developer’s Guide - Expression Filter provides usage and reference information about Expression Filter, a feature of Oracle Database that stores, indexes, and evaluates conditional expressions in relational tables Audience Application developers and DBAs can save time and labor by using Oracle Expression Filter to store and evaluate large sets of conditional expressions in the database Conditional expressions... validate expressions and suggest optimal index structure Oracle Expression Filter Concepts 1-1 What Is Expression Filter? I Expression indexing: Enhances performance of the EVALUATE operator for large expression sets Expression indexing is available in Oracle Database Enterprise Edition 1.1.1 Expression Filter Usage Scenarios The following sections are examples of how you can use Expression Filter Match... of the Oracle online documentation 1-1 4 Oracle Database Application Developer’s Guide - Expression Filter 2 Indexing Expressions Expression indexing is available only in Oracle Database Enterprise Edition Note: An index can be defined on a column storing expressions to quickly find expressions that evaluate to true for a data item This is most helpful when a large expression set is evaluated for a data... compare expressions to incoming data items See Section 1.3 Oracle Database Application Developer’s Guide - Expression Filter Introduction to Expressions The remaining sections in this chapter guide you through this procedure 1.2.1 Defining Attribute Sets A special form of an Oracle object type is used to create an attribute set (For more information about object types, see Oracle Database Application. .. prior to upgrading xv xvi 1 Oracle Expression Filter Concepts Oracle Expression Filter is a feature of Oracle Database that allows application developers to store, index, and evaluate conditional expressions (expressions) in one or more columns of a relational table Expressions are a useful way to describe interests in expected data Expression Filter matches incoming data with expressions stored in a column... "ADD_ELEMENTARY_ATTRIBUTE Procedure" in Chapter 8 1-6 Oracle Database Application Developer’s Guide - Expression Filter Introduction to Expressions If the expressions refer to user-defined functions, you must add the functions to the corresponding attribute set Example 1–3 shows how to add user-defined functions, using the ADD_FUNCTIONS procedure, to an attribute set Example 1–3 Adding User-Defined Functions to an Attribute... nedc-doc_us @oracle. com FAX: 603.897.3825 Attn: Expression Filter Documentation Postal service: Oracle Corporation Expression Filter Documentation One Oracle Drive Nashua, NH 0306 2-2 804 USA If you would like a reply, please provide your name and contact information If you have problems with the software, please contact your local Oracle Support Services xi xii Preface Oracle Database Application Developer’s. .. is converted into a disjunctive-normal form (disjunction of conjunctions), and each disjunction in this normal form is treated as a separate expression with the same identifier as the original expression The predicate table contains one row for each such disjunction 2-2 Oracle Database Application Developer’s Guide - Expression Filter Index Representation The Expression Filter index can be tuned for... interests (in trading cars) being captured in a Consumer table 1-8 Oracle Database Application Developer’s Guide - Expression Filter Introduction to Expressions Figure 1–1 Expression Datatype Elementary Attributes Model VARCHAR2(30) Price NUMBER Mileage NUMBER Year NUMBER Attribute Set: Car4Sale Oracle Supplied Functions UPPER LOWER User-Defined Functions CrashTestRating HorsePower CId Zipcode Phone... predicate group are: I One-time computation of the left-hand side of the predicate group I One or more range scans on the bitmap indexes using the computed value The steps involved in evaluating the predicates in a stored predicate group are: I 2-6 One-time computation of the left-hand side of the predicate group Oracle Database Application Developer’s Guide - Expression Filter . Oracle Database Application Developer’s Guide - Expression Filter 10g Release 1 (10.1) Part No. B1082 1-0 1 December 2003 Oracle Database Application Developer’s. upgrading. xvi Oracle Expression Filter Concepts 1-1 1 Oracle Expression Filter Concepts Oracle Expression Filter is a feature of Oracle Database that allows application