Converting data on insertion – Sybase 12.4.2 User Manual

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Converting data on insertion

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213 NULL 190 152.00 1

24 NULL 215 172.00 2

(2 rows affected)

If you later load data from another file into

ps_partkey

and

ps_availqty

,

insertions begin correctly at the next row, as shown below.

LOAD TABLE partsupp

(ps_partkey ASCII(6),

ps_availqty ASCII(6),

FILLER(2))

FROM ’C:\\iq\\archive\\mill2.txt’

SELECT *, rowid(partsupp) FROM partsupp

ps_partkey ps_suppkey ps_availqty ps_value rowid(partsupp)

---------- ---------- ----------- -------- ---------------

213 NULL 190 152.00 1

24 NULL 215 172.00 2

28 NULL 490 NULL 3

211 NULL 15 NULL 4

(4 rows affected)

To calculate and insert the values for

ps_value

, you need to repeat the

INSERT

statement shown earlier in this example, changing the

START ROW ID

value to

the new row number, 3.

Previewing partial-
width inserts

Given the possibility of errors if you do a partial-width insert incorrectly, it is
a good idea to preview these inserts. The

PREVIEW

load option lets you see

the layout of input in the destination table. This option is available in

LOAD

TABLE

, but not in the

INSERT

command.

Converting data on insertion

The data you enter into your Adaptive Server IQ database will likely come
from diverse sources. Not all of your data will match the Adaptive Server IQ
data types exactly. Some of it will need to be converted. Data is converted in
two ways: explicitly and implicitly. For example, to insert

CHAR

data into an

INT

column you must convert it explicitly.

Implicit conversions can occur:

When you insert data selected from another column in the same database

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