Developer. 1 enterprise. Professional Guide. Oracle Advanced PL/SQL. example questions for 1Z0-146 examination

Transcription

1 Oracle Advanced PL/SQL Developer Professional Guide Master advanced PL/SQL concepts along with plenty of example questions for 1Z0-146 examination Saurabh K. Gupta [ 1 enterprise I professional expertise distilled 88 PUBLISHING - BIRMINGHAM MUMBAI

2 Preface 1 Chapter 1: Overview of PL/SQL Programming Concepts 9 PL/SQL the procedural aspect 10 My first PL/SQL program 11 PL/SQL development environments 13 SQL Developer 13 SQL Developer the history 15 Creating a connection 15 SQL Worksheet 16 Executing a SQL statement 18 Calling a SQL script from SQL Developer 19 Creating and executing an anonymous PL/SQL block 21 Debugging the PL/SQL code 21 Editing and saving the scripts 23 SQL*Plus 24 Executing a SQL statement in SQL*Plus 26 Executing an anonymous PL/SQL block 26 Procedures 27 Executing a procedure 28 Functions 29 Function execution methods 31 Restrictions on calling functions from SQL expressions 32 PL/SQL packages 33 Cursors an overview 35 Cursor execution cycle 35 Cursor attributes 36 Cursor FOR loop 38 Exception handling in PL/SQL 39 System-defined exceptions 39 User-defined exceptions 41

3 The RAISE_APPLICATION_ERROR procedure 43 Exception propagation 46 Managing database dependencies 48 Displaying the direct and indirect dependencies 49 Dependency metadata 50 Dependency issues and enhancements 50 Reviewing Oracle-supplied packages 51 Summary 52 Practice exercise 52 Chapter 2: Designing PL/SQL Code 55 Understanding cursor structures 55 Cursor execution cycle 56 Cursor design considerations 57 Cursor design guidelines 58 Cursor attributes 59 Implicit cursors 60 Explicit cursors 62 Cursor variables 66 Ref cursor types strong and weak 69 SYS_REFCURSOR 69 Processing a cursor variable 70 Cursor variables as arguments 71 Cursor variables restrictions 73 Subtypes 74 Subtype classification 75 Oracle's predefined subtypes 75 User-defined subtypes 76 Type compatibility with subtypes 77 Summary 78 Practice exercise 78 Chapter 3: Using Collections 81 Collections an overview 82 Categorization 83 Selecting an appropriate collection type 84 Associative arrays 84 Nested tables 88 Nested table collection type as the database object 90 DML operations on nested table columns 91 A nested table collection type in PL/SQL 93 Additional features of a nested table 94 Varray 98

4 Varray in PL/SQL 99 Varray as a database collection type 100 DML operations on varray type columns 100 Collections a comparative study 103 Common characteristics of collection types 103 Nested table versus associative arrays 104 Nested table versus varrays 105 PL/SQL collection methods 105 EXISTS 105 COUNT 106 LIMIT 107 FIRST and LAST 108 PRIOR and NEXT 109 EXTEND 109 TRIM 111 DELETE 112 Manipulating collection elements 113 Collection initialization 115 Summary 117 Practice exercise 117 Chapter 4: Using Advanced Interface Methods 121 Understanding external routines 122 Architecture of external routines 122 Oracle Net Configuration 125 TNSNAMES.ora 125 LISTENER.ora 126 Oracle Net Configuration verification 129 Benefits of external procedures 130 Executing external C programs from PL/SQL 131 Executing C program through external procedure development steps 131 Executing Java programs from PL/SQL 136 Calling a Java class method from PL/SQL 137 Uploading a Java class into the database development steps 137 The loadjava utility an Creating packages for Java class methods 140 Summary 141 Practice exercise 141 illustration 137 Chapter 5: Implementing VPD with Fine Grained Access Control 145 Fine Grained Access Control 146 Overview 146 Virtual Private Database the alias 147

5 How FGAC or VPD works? 147 Salient features of VPD 148 VPD implementation outline and components 149 Application context 150 Policy function definition and implementation of row-level security 153 Associating a policy using the DBMS_RLS package 155 VPD implementation demonstrations 156 Assignment 1 implementing VPD using simple security policy 157 Assignment 2 implementing VPD using an application context 159 VPD policy metadata 163 Policy utilities refresh and drop 164 Summary 165 Practice exercise 165 Chapter 6: Working with Large Objects 169 Introduction to the LOB data types 170 Internal LOB 171 External LOB 171 Understanding the LOB data types 172 LOB value and LOB locators 172 BLOBorCLOB! 172 BFILE 173 Temporary LOBs 173 Creating LOB data types 173 Directories 173 Creating LOB data type columns in a table 175 Managing LOB data types 177 Managing internal LOBs 178 Securing and managing BFILEs 178 The DBMSJ.OB package overview 179 Security model 179 DBMSJ-OB constants 180 DBM S_LOB data types 180 DBMSJ-OB subprograms 181 Rules and regulations 182 Working with the CLOB, BLOB, and BFILE data types 183 Initializing LOB data type columns 184 Inserting data into a LOB column 185 Populating a LOB data type using an external file 185 Selecting LOB data 189 Modifying the LOB data 190 Delete LOB data 192 Miscellaneous LOB notes 192

6 LOB column states 193 Locking a row containing LOB 193 Opening and closing LOBs 193 Accessing LOBs 193 LOB restrictions 194 Migrating from LONG to LOB 194 Using temporary LOBs 196 Temporary LOB operations 196 Managing temporary LOBs 197 Validating, creating, and freeing a temporary LOB 198 Summary 200 Practice exercise 200 Chapter 7: Using SecureFile LOBs 205 Introduction to SecureFiles 206 SecureFile LOB an overview 207 Architectural enhancements in SecureFiles 208 SecureFile LOB features 210 Working with SecureFiles 211 SecureFile metadata 213 Enabling advanced features in SecureFiles 214 Deduplication 214 Compression 215 Encryption 216 Migration from BasicFiles to SecureFiles 220 Online Redefinition method 221 Summary 224 Practice exercise 225 Chapter 8: Compiling and Tuning to Improve Performance 227 Native and interpreted compilation techniques 228 Real native compilation 229 Selecting the appropriate compilation mode 230 When to choose interpreted compilation mode? 230 When to choose native compilation mode? 231 Setting the compilation mode 231 Querying the compilation settings 232 Compiling a program unit for a native or interpreted compilation 233 Compiling the database for PL/SQL native compilation (NCOMP) 235 Tuning PL/SQL code 238 Comparing SQL and PL/SQL 239 Avoiding implicit data type conversion 239 Understanding the NOT NULL constraint 241 Using the PLSJNTEGER data type for arithmetic operations 243

7 Using a SIMPLEJ NTEGER data type 245 Modularizing the PL/SQL code 246 Using bulk binding 248 Using SAVE_EXCEPTIONS 252 Rephrasing the conditional control statements 254 Conditions with an OR logical operator 254 Conditions with an AND logical operator 254 Enabling intra unit inlining 255 PLSQL_OPTIMIZE_LEVEL the Oracle initialization parameter 256 Case 1 PLSQL_OPTIMIZE_LEVEL = Case 2 PLSQL_OPTIMIZE_LEVEL = Case 3 PLSQL_OPTIMIZE_LEVEL = Case 4 PLSQL_OPTIMIZE_LEVEL = PRAGMA INLINE 262 Summary 265 Practice exercise 265 Chapter 9: Caching to Improve Performance 269 Introduction to result cache 270 Server-side result cache 271 SQL query result cache 272 PL/SQL function result cache 272 OCI client results cache 273 Configuring the database for the server result cache 273 The DBMS_RESULT_CACHE package 276 Implementing the result cache in SQL 277 Manual result cache 277 Automatic result cache 279 Result cache metadata 281 Query result cache dependencies 283 Cache memory statistics 283 Invalidation of SQL result cache 284 Displaying the result cache memory report 286 Read consistency of the SQL result cache 287 Limitation of SQL result cache 287 Implementing result cache in PL/SQL 288 The RESULT_CACHE clause 288 Cross-session availability of cached results 292 Invalidation of PL/SQL result cache 292 Limitations of PL/SQL function result cache 294 Argument and return type restrictions 294 Function structural restrictions 294 Summary 295 Practice exercise 295

8 Chapter 10: Analyzing PL/SQL Code 299 Track coding information 299 [DBA ALL USERLARGUMENTS 301 [DBA ALL USERLOBJECTS 304 [DBA ALL USER]_SOURCE 306 [DBA ALL USER]_PROCEDURES 307 [DBA ALL USERLDEPENDENCIES 308 Using SQL Developer to find coding information 310 The DBMS_DESCRIBE package 313 DBMS_UTILITY.FORMAT_CALL_STACK 316 Tracking propagating exceptions in PL/SQL code 318 Determining identifier types and usages 319 The PL/Scope tool 320 The PL/Scope identifier collection 320 The PUScope report 322 Illustration 322 Applications of the PL/Scope report 325 The DBMS_METADATA package 326 DBMS_METADATA data types and subprograms 327 Parameter requirements 330 The DBMS_METADATA transformation parameters and filters 330 Working with DBMS_METADATA illustrations 332 Case 1 retrieve the metadata of a single object 332 Case 2 retrieve the object dependencies on the F_GET LOC function 335 Case 3 retrieve system grants on the ORADEV schema 335 Case 4 retrieve objects of function type in the ORADEV schema 336 Summary 337 Practice exercise 337 Chapter 11: Profiling and Tracing PL/SQL Code 339 Tracing the PL/SQL programs 340 The DBMS TRACE package 341 Installing DBMS_TRACE 341 DBMS_TRACE subprograms 341 The PLSQL_DEBUG parameter and the DEBUG option 343 Viewing the PL/SQL trace information 344 Demonstrating the PL/SQL tracing 347 Profiling the PL/SQL programs 350 Oracle hierarchical profiler the DBMS_HPROF package 351 View profiler information 352 Demonstrating the profiling of a PL/SQL program 352 The plshprof utility 357 Sample reports 359

9 Table ofcontents Summary 361 Practice exercise 361 Chapter 12: Safeguarding PL/SQL Code against SQL Injection Attacks 365 SQL injection an introduction 366 SQL injection an Types of SQL injection overview 366 attacks 369 Preventing SQL injection attacks 369 Immunizing SQL injection attacks 370 Reducing the attack's surface 370 Controlling user privileges 371 Invoker's and definer's rights 371 Avoiding dynamic SQL 375 Bind arguments 378 Sanitizing inputs using DBMS_ASSERT 379 The DBMS_ASSERT package 380 Testing the code for SQL injection flaws 386 Test strategy 386 Reviewing the code 386 Static code analysis 387 Fuzz tools 387 Generating test cases 387 Summary 388 Practice exercise 388 Appendix: Answers to Practice Questions 391 Chapter 1, Overview of PL/SQL Programming Concepts 391 Chapter 2, Designing PL/SQL Code 392 Chapter 3, Using Collections 393 Chapter 4, Using Advanced Interface Methods 394 Chapter 5, Implementing VPD with Fine Grained Access Control 395 Chapter 6, Working with Large Objects 396 Chapter 7, Using SecureFile LOBs 397 Chapter 8, Compiling and Tuning to Improve Performance 398 Chapter 9, Caching to Improve Performance 400 Chapter 10, Analyzing PL/SQL Code 401 Chapter 11, Profiling and Tracing PL/SQL Code 401 Chapter 12, Safeguarding PL/SQL Code against SQL Injection Attacks 402 Index 405