Oracle Built−in Packages- P1 ppt

[Appendix A] What's on the Companion Disk?
Table of Contents
A. What's on the Companion Disk? 2
A.1 Installing the Guide 2
3
A.2 Using the Guide 3
4
1. Introduction 5
1.1 The Power of Built−in Packages 5
1.1.1 A Kinder , More Sharing Oracle 6
7
1.2 Built−in Packages Covered in This Book 7
1.2.1 Application Development Packages 10
1.2.2 Server Management Packages 11
1.2.3 Distributed Database Packages 12
14
1.3 Using Built−in Packages 14
1.3.1 What Is a Package? 14
1.3.2 Controlling Access with Packages 15
1.3.3 Referencing Built−in Package Elements 17
1.3.4 Exception Handling and Built−in Packages 18
1.3.5 Encapsulating Access to the Built−in Packages 24
1.3.6 Calling Built−in Packaged Code from Oracle Developer/2000 Release 1 27
1.3.7 Accessing Built−in Packaged Technology from Within SQL 30
38
1.4 Examining Built−in Package Source Code 38
1.4.1 The STANDARD Package 39
1.4.2 The DBMS_STANDARD Package 40
42
2. Executing Dynamic SQL and PL/SQL 43
2.1 Examples of Dynamic SQL 43

46
2.2 Getting Started with DBMS_SQL 46
2.2.1 Creating the DBMS_SQL Package 46
2.2.2 Security and Privilege Issues 46
2.2.3 DBMS_SQL Programs 46
2.2.4 Types of Dynamic SQL 47
2.2.5 DBMS_SQL Exceptions 49
2.2.6 DBMS_SQL Nonprogram Elements 49
52
2.3 The DBMS_SQL Interface 52
2.3.1 Processing Flow of Dynamic SQL 52
2.3.2 Opening the Cursor 54
2.3.3 Parsing the SQL Statement 55
2.3.4 Binding Values into Dynamic SQL 58
2.3.5 Defining Cursor Columns 63
2.3.6 Executing the Cursor 66
2.3.7 Fetching Rows 66
2.3.8 Retrieving Values 69
2.3.9 Closing the Cursor 76
2.3.10 Checking Cursor Status 77
2.3.11 Describing Cursor Columns 80
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Table of Contents
2.4 Tips on Using Dynamic SQL 85
2.4.1 Some Restrictions 85
2.4.2 Privileges and Execution Authority with DBMS_SQL 85
2.4.3 Combining Operations 87
2.4.4 Minimizing Memory for Cursors 88

2.4.5 Improving the Performance of Dynamic SQL 89
2.4.6 Problem−Solving Dynamic SQL Errors 91
2.4.7 Executing DDL in PL/SQL 94
2.4.8 Executing Dynamic PL/SQL 94
97
2.5 DBMS_SQL Examples 97
2.5.1 A Generic Drop_Object Procedure 97
2.5.2 A Generic Foreign Key Lookup Function 98
2.5.3 A Wrapper for DBMS_SQL .DESCRIBE_COLUMNS 104
2.5.4 Displaying Table Contents with Method 4 Dynamic SQL 107
2.5.5 Indirect Referencing in PL/SQL 116
2.5.6 Array Processing with DBMS_SQL 121
2.5.7 Using the RETURNING Clause in Dynamic SQL 134
138
3. Intersession Communication 139
3.1 DBMS_PIPE: Communicating Between Sessions 139
3.1.1 Getting Started with DBMS_PIPE 140
3.1.2 How Database Pipes Work 141
3.1.3 Managing Pipes and the Message Buffer 143
3.1.4 Packing and Unpacking Messages 149
3.1.5 Sending and Receiving Messages 158
3.1.6 Tips on Using DBMS_PIPE 161
3.1.7 DBMS_PIPE Examples 164
184
3.2 DBMS_ALERT: Broadcasting Alerts to Users 184
3.2.1 Getting Started with DBMS_ALERT 184
3.2.2 The DBMS_ALERT Interface 185
3.2.3 DBMS_ALERT Examples 191
202
4. User Lock and Transaction Management 203

4.1 DBMS_LOCK: Creating and Managing Resource Locks 203
4.1.1 Getting Started with DBMS_LOCK 203
4.1.2 The DBMS_LOCK Interface 205
4.1.3 Tips on Using DBMS_LOCK 211
4.1.4 DBMS_LOCK Examples 213
221
4.2 DBMS_TRANSACTION: Interfacing to SQL Transaction Statements 221
4.2.1 Getting Started with DBMS_TRANSACTION 221
4.2.2 Advising Oracle About In−Doubt Transactions 223
4.2.3 Committing Data 224
4.2.4 Rolling Back Changes 225
4.2.5 Setting Transaction Characteristics 227
4.2.6 Cleaning Up Transaction Details 229
4.2.7 Returning Transaction Identifiers 231
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Table of Contents
5. Oracle Advanced Queuing 235
5.1 Oracle AQ Concepts 236
5.1.1 General Features 236
5.1.2 Enqueue Features 237
5.1.3 Dequeue Features 238
5.1.4 Propagation Features 238
5.1.5 A Glossary of Terms 240
5.1.6 Components of Oracle AQ 243
5.1.7 Queue Monitor 244
5.1.8 Data Dictionary Views 244
245
5.2 Getting Started with Oracle AQ 245

5.2.1 Installing the Oracle AQ Facility 245
5.2.2 Database Initialization 246
5.2.3 Authorizing Accounts to Use Oracle AQ 247
249
5.3 Oracle AQ Nonprogram Elements 249
5.3.1 Constants 249
5.3.2 Object Names 250
5.3.3 Queue Type Names 251
5.3.4 Agents Object Type 251
5.3.5 Recipient and Subscriber List Table Types 252
5.3.6 Message Properties Record Type 252
5.3.7 Enqueue Options Record Type 254
5.3.8 Dequeue Options Record Type 255
5.3.9 Oracle AQ Exceptions 257
259
5.4 DBMS_AQ: Interfacing to Oracle AQ (Oracle8 only) 259
5.4.1 Enqueuing Messages 259
5.4.2 Dequeuing Messages 262
268
5.5 DBMS_AQADM: Performing AQ Administrative Tasks (Oracle8 only) 268
5.5.1 Creating Queue Tables 269
5.5.2 Creating and Starting Queues 272
5.5.3 Managing Queue Subscribers 276
5.5.4 Stopping and Dropping Queues 278
5.5.5 Managing Propagation of Messages 280
5.5.6 Verifying Queue Types 282
5.5.7 Starting and Stopping the Queue Monitor 283
284
5.6 Oracle AQ Database Objects 284
5.6.1 Objects Per Queue Table 284

5.6.2 Data Dictionary Objects 287
290
5.7 Oracle AQ Examples 290
5.7.1 Improving AQ Ease of Use 291
5.7.2 Working with Prioritized Queues 293
5.7.3 Building a Stack with AQ Using Sequence Deviation 297
5.7.4 Browsing a Queue's Contents 299
5.7.5 Searching by Correlation Identifier 303
5.7.6 Using Time Delay and Expiration 307
5.7.7 Working with Message Groups 313
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Table of Contents
5.7.8 Working with Multiple Consumers 316
322
6. Generating Output from PL/SQL Programs 323
6.1 DBMS_OUTPUT: Displaying Output 323
6.1.1 Getting Started with DBMS_OUTPUT 323
6.1.2 Enabling and Disabling Output 326
6.1.3 Writing to the DBMS_OUTPUT Buffer 328
6.1.4 Retrieving Data from the DBMS_OUTPUT Buffer 329
6.1.5 Tips on Using DBMS_OUTPUT 332
6.1.6 DBMS_OUTPUT Examples 333
337
6.2 UTL_FILE: Reading and Writing Server−side Files 337
6.2.1 Getting Started with UTL_FILE 337
6.2.2 Opening Files 343
6.2.3 Reading from Files 345
6.2.4 Writing to Files 346
6.2.5 Closing Files 350

6.2.6 Tips on Using UTL_FILE 351
6.2.7 UTL_FILE Examples 358
365
7. Defining an Application Profile 366
7.1 Getting Started with DBMS_APPLICATION_INFO 366
7.1.1 DBMS_APPLICATION_INFO Programs 366
7.1.2 The V$ Virtual Tables 367
7.1.3 DBMS_APPLICATION_INFO Nonprogram Elements 367
369
7.2 DBMS_APPLICATION_INFO Interface 369
7.2.1 The DBMS_APPLICATION_INFO.READ_CLIENT_INFO procedure 369
7.2.2 The DBMS_APPLICATION_INFO.READ_MODULE procedure 369
7.2.3 The DBMS_APPLICATION_INFO.SET_ACTION procedure 370
7.2.4 The DBMS_APPLICATION_INFO.SET_CLIENT_INFO procedure 372
7.2.5 The DBMS_APPLICATION_INFO.SET_MODULE procedure 373
7.2.6 The DBMS_APPLICATION_INFO.SET_SESSION_LONGOPS procedure 374
377
7.3 DBMS_APPLICATION_INFO Examples 377
7.3.1 About the register_app Package 377
7.3.2 The action Procedure 378
7.3.3 The set_stats Procedure 378
7.3.4 The Information Procedures 380
7.3.5 Using the register_app Package 381
7.3.6 Covering DBMS_APPLICATION_INFO 382
7.3.7 Monitoring Application SQL Resource Consumption 384
7.3.8 Session Monitoring and Three−Tier Architectures 384
7.3.9 Tracking Long−Running Processes 385
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8. Managing Large Objects 390
8.1 Getting Started with DBMS_LOB 390

8.1.1 DBMS_LOB Programs 390
8.1.2 DBMS_LOB Exceptions 392
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