Cursors: Accessing Data Row by Row

A cursor accesses the results of a SQL select statement one or more rows at a time. Cursors allow you to modify or delete rows on an individual basis.

For information on how cursors affect performance, see the Performance and Tuning Guide.

How cursors work

How Adaptive Server processes cursors

Declaring cursors

declare cursor syntax

Types of cursors

Cursor scope

Cursor scans and the cursor result set

Making cursors updatable

Determining which columns can be updated

Opening cursors

Fetching data rows using cursors

fetch syntax

Checking the cursor status

Getting multiple rows with each fetch

Checking the number of rows fetched

Updating and deleting rows using cursors

Updating cursor result set rows

Deleting cursor result set rows

Closing and deallocating cursors

An example using a cursor

Using cursors in stored procedures

Cursors and locking

Cursor locking options

Getting information about cursors

Using browse mode instead of cursors

Browsing a table

Browse-mode restrictions

Timestamping a new table for browsing

Timestamping an existing table

Comparing timestamp values

Join cursor processing and data modifications

Updates and deletes that can affect the cursor position

Cursor positioning after a delete or update command without joins

Effects of updates and deletes on join cursors

Effects of join column buffering on join cursors

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