IBM 000-8697 Database and Table Migration

Data Consistency, Recovery, and Migration 4-53
Database and Table Migration
The correct method for you depends on your processing environment and
whatyou want to move (a database, selected tables, or selected columns from
selected tables). The table displayed inFigure 4-9 compares the advantages
and different characteristics of each migration method. The sections that
follow describe and compare each migration method in detail. (Refer to
Chapter 7, “Utilities,” for a complete discussion of each OnLine utility. The
LOAD andUNLOAD statements are documented in the DB-AccessUser ’s
Manual.)
Figure4-9
Quick comparison of migration methods
UNLOAD/
LOAD UNLOAD/ dbload dbexport/ dbimport tbunload/ tbload
Performance Moderate Moderate Moderate Fast
Ease of use Input must
adhere to
format
You must
build input
file
No initial
requirements No initial requirements
Flexibility
built into
options
No Yes Yes Yes
Ability to
modify data
schema
Modify the
ASCII file
created by
dbschema
Modify.sql
file No ability to modify No ability to modify
Granularity of
data
Aportion ofa
field up to a
complete
table
A portion of a
field up to a
completetable
Database only Table or
database
Output
destination
Must have
enough disk
spacefor data
Must have
enough disk
space for data
Disk or Tape Tape only