Sybase 12.4.2 manual Permissions for modifying data, Scheduling database updates, 173

CHAPTER 5 Moving Data In and Out of Databases

Specifying an output format for Interactive SQL

You can set the DBISQL output format in three ways:

•Select Command → Options from the DBISQL menu bar, and then choose an Output Format from the dropdown list. To make this the default output format, click Permanent.

•Specify the DBISQL option, OUTPUT_FORMAT, to set the default output format.

For syntax details see the Adaptive Server IQ Reference Manual.

Permissions for modifying data

You can only execute data modification statements if you have the proper permissions on the database tables you want to modify. The database administrator and the owners of database objects use the GRANT and REVOKE statements to decide who has access to which data modification functions.

To insert data, you need INSERT permission for that table or view. To delete data, you need DELETE permission for that table or view. To update data, you need UPDATE permission. The DBA can insert into or delete from any table. The owner of a table has INSERT, DELETE, and UPDATE permission on it.

Permissions can be granted to and revoked from individual users, groups, or the public group. For more information on permissions, see Chapter 10, “Managing User IDs and Permissions”.

Scheduling database updates

Multiple users can query a database table while one user inserts data into that table. Multiple users can update the database concurrently, as long as they are inserting into or deleting from different tables.

When you allow concurrent use of the database during updates, you pay a penalty in performance and disk use. For an explanation of how Adaptive Server IQ handles concurrency issues, see Chapter 8, “Transactions and Versioning” For other suggestions on improving load performance, see “Tuning bulk loading of data”

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