Index_D

---

D

Data access methods, 240–41, 256–301 see also Indexing

cluster and hash scans, 281–82

full table scans, 256–66

reading deleted rows, 262–64

using PARALLEL, 264–66

index scans, 268–81

bitmap join, 281

COUNT function, 277

DISTINCT clause, 276–77

fast full scan, 275–76

full scan, 272–75

index join, 280

IS NOT NULL comparison, 277–78

parallel scan, 278–80

range scan, 269–71

skip scan, 271–72

unique scan, 269

joining tables, 282–301

cartesian join, 298

hash join, 289–90

join order execution, 283

mutable join nesting, 293–97

nested loop join, 285–89

outer join, 299–301

semi join, 297–98

sort merge join, 290–93

types of join, 283–85

ROWID scans, 267

sample table scans, 266–67

Data definition language see DDL

Data manipulation language see DML

Data model, definition, xii–xiii

Database Configuration Assistant see Creating a database

Database samples, 695–718

active concurrent database scripting, 695–712

internet OLTP and reporting simulation, 706–13

internet OLTP database simulation, 695–706

partitioning tablespace creation, 716–17

schemas, 695, 696, 697, 698, 699

updating summary fields, 713–16

DDL (data definition language), definition, 99–100

Denormalization of a database, 61–80

adding composite keys, 67–68

definition, 64

mutable and complex joins, 65–68

by reversing normal forms, 70–74

employees schema, 73

2nd normal form, 74

3rd normal form, 72

4th normal form, 71

useful tricks, 74–79

application caching, 79

copying columns between entities, 75–76

placing summary columns into parent entities, 76–77

separating active and inactive data, 77–78

using views, 78–79

using Oracle database objects, 79–80

DML (data manipulation language), definition, 99–100, 228–30

---