Bulk loading data using the load table statement, Null value output – Sybase 12.4.2 User Manual

Page 195

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CHAPTER 5 Moving Data In and Out of Databases

175

Redirecting output
and messages

The

>&

redirection symbol redirects all output including error messages and

statistics for the command on which it appears. For example:

SELECT *

FROM employee

>& empfile

Do not enclose the file name in quotation marks.

This example outputs the

SELECT

statement to the file empfile, followed by the

output from the

SELECT

statement and some statistics pertaining to the

command.

The >& redirection method is useful for getting a log of what happens during
a

READ

command. The statistics and errors of each command are written

following the command in the redirected output file.

NULL value output

The most common reason to extract data is for use in other software products.
The other software package may not understand NULL values, however.

The DBISQL option

NULLS

allows you to choose how NULL values are

output. Alternatively, you can use the

IFNULL

function to output a specific

value whenever there is a NULL value.

For information on setting DBISQL options, see “SET OPTION statement” in
Adaptive Server IQ Reference Manual.

Bulk loading data using the LOAD TABLE statement

The

LOAD TABLE

statement is used for efficient importing of data from a text

or binary file into an existing database table. It loads data into any column
indexes you have defined, as well as any created automatically.

In order to use the

LOAD TABLE

statement, you need INSERT permission on

the table.

See the description of the

ON FILE ERROR

load option for what happens when

errors occur during a load.

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