Specify NOT NULL in a WHERE Clause If the Column Was Not Declared NOT NULL....... 5-18 Example: Setting Up a French Linguistic Index .................................................................. 5-19 Searching Linguistic Strings ............................................................................................................... 5-19 SQL Regular Expressions in a Multilingual Environment ........................................................... 5-19 Character Range '[x-y]' in Regular Expressions.......................................................................... 5-20 Collation Element Delimiter '[. .]' in Regular Expressions ........................................................ 5-20 Character Class '[: :]' in Regular Expressions .............................................................................. 5-21 Equivalence Class '[= =]' in Regular Expressions....................................................................... 5-21 Examples: Regular Expressions .................................................................................................... 5-21
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Supporting Multilingual Databases with Unicode Overview of Unicode............................................................................................................................... 6-1 What is Unicode?...................................................................................................................................... 6-1 Supplementary Characters ............................................................................................................... 6-2 Unicode Encodings ............................................................................................................................ 6-2 UTF-8 Encoding .......................................................................................................................... 6-2 UCS-2 Encoding .......................................................................................................................... 6-3 UTF-16 Encoding ........................................................................................................................ 6-3 Examples: UTF-16, UTF-8, and UCS-2 Encoding ................................................................... 6-3 Oracle's Support for Unicode ........................................................................................................... 6-4 Implementing a Unicode Solution in the Database .......................................................................... 6-4 Enabling Multilingual Support with Unicode Databases ............................................................ 6-5 Enabling Multilingual Support with Unicode Datatypes ............................................................ 6-6 How to Choose Between a Unicode Database and a Unicode Datatype Solution ................... 6-7 When Should You Use a Unicode Database? ......................................................................... 6-7 When Should You Use Unicode Datatypes?........................................................................... 6-8 Comparing Unicode Character Sets for Database and Datatype Solutions .............................. 6-8 Unicode Case Studies ........................................................................................................................... 6-10 Designing Database Schemas to Support Multiple Languages................................................... 6-12 Specifying Column Lengths for Multilingual Data.................................................................... 6-12 Storing Data in Multiple Languages ............................................................................................ 6-13 Store Language Information with the Data ......................................................................... 6-13 Select Translated Data Using Fine-Grained Access Control ............................................. 6-13 Storing Documents in Multiple Languages in LOB Datatypes ................................................ 6-14 Creating Indexes for Searching Multilingual Document Contents ......................................... 6-15 Creating Multilexers ................................................................................................................ 6-15 Creating Indexes for Documents Stored in the CLOB Datatype ...................................... 6-16 Creating Indexes for Documents Stored in the BLOB Datatype....................................... 6-16
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Programming with Unicode Overview of Programming with Unicode ........................................................................................... Database Access Product Stack and Unicode ................................................................................ SQL and PL/SQL Programming with Unicode................................................................................... SQL NCHAR Datatypes.................................................................................................................... The NCHAR Datatype ...............................................................................................................
7-1 7-1 7-3 7-4 7-4
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