U

UDB database, 572

UNCATALOG DATABASE, 185–186

UNCATALOG DCS DATABASE, 189

Uncommitted Read isolation level, 325, 468, 469t, 474–476, 475, 498, 499, 501, 610, 611, 613

Unfenced UDFs, 113

UNION set operator, 307, 307, 591, 596

UNION ALL set operator, 308, 308, 357, 591

UNIQUE clause, 211, 435, 582

UNIQUE constraint, 365, 374, 379–381, 380, 384, 403, 406, 408, 410, 421, 426, 456, 457, 602, 605

Unique key, referential integrity constraints and 384t

Unit of work, 322, 349–350, 361, 466, 596. See also transactions and transaction boundaries, 322

Universal Developer's Edition, DB2, 36, 48, 568

UNIX, 49, 54, 568

authentication and, 102

buffer pools in, 169

Database Connection Services (DCS) directory in, 181–182, 249

privileges and, 119, 133, 135, 145

UNLOAD utility, 7

Updatable cursors, 315

UPDATE, 67, 116, 117, 123, 129, 130, 134, 139, 140, 144, 149t, 156, 158, 257, 261–263, 262t, 347, 359, 569, 574, 576, 577, 584, 588, 593, 596, 608

locks and, 486t

NULL and, 263

ON UPDATE NO ACTION and, 389–391, 391

ON UPDATE RESTRICT and, 389–391, 390

positioned update operations and, 263

referential integrity constraints and, 385, 389–391, 390, 391

searched update operations and, 263

SELECT and, 262

transactions and, 326

triggers and, 225

Update Rule for referential integrity constraint and, 389–391, 390, 391

values specified for, 263

WHERE clause and, 262, 263

XML and, 333, 334

Update (U) lock, 481t, 486t, 488t, 489, 500, 612

Update Rule, referential integrity constraints and, 389–391, 390, 391

UPDATE trigger, 582

USAGE, 119, 131, 135, 141, 145, 159

USE privilege, 114, 115, 124, 171

User Analyst, authorities and privileges using, 150t

User IDs, 98–99, 190, 191

User management, 11

User-defined data types, 192, 225–228, 373–374, 444

casting functions and, 227–228

comparison functions and, 227

Control Center to create, 226, 226, 227

Create Distinct Type dialog for, 226, 226, 227

CREATE DISTINCT TYPE for, 225–226

CREATE TYPE for, 228

DISTINCT clause and, 227

distinct, 225–228

GROUP BY and, 227

ORDER BY and, 227

SELECT and, 227

strong data typing and, 225

structured, 228

subtypes and, 228

supertypes and, 228

User-defined functions (methods), 10, 192, 228–230, 249, 255, 329–331, 352, 363, 582, 598

CREATE FUNCTION and, 230

CREATE_EXTERNAL_ROUTINE and, 113, 127, 137, 149t

CREATE_NOT_FENCED_ROUTINE and, 113–114, 127, 137

external scalar, 229, 330

external table, 229, 330

fenced vs. unfenced, 113

OLE DB external table, 229–230, –331 229

sourced (template), 229, 330

SQL scalar, table, row, 229, 330

stored procedures and, 230

User-defined routines, 586

USERSPACE1, 169

Utilities, 7

Utility programs SQL and, 170