FETCH (Transact-SQL)
Retrieves a specific row from a Transact-SQL server cursor.
Syntax
FETCH
[ [ NEXT | PRIOR | FIRST | LAST
| ABSOLUTE { n | @nvar }
| RELATIVE { n | @nvar }
]
FROM
]
{ { [ GLOBAL ] cursor_name } | @cursor_variable_name }
[ INTO @variable_name [ ,...n ] ]
Arguments
- NEXT
Returns the result row immediately following the current row and increments the current row to the row returned. If FETCH NEXT is the first fetch against a cursor, it returns the first row in the result set. NEXT is the default cursor fetch option.
- PRIOR
Returns the result row immediately preceding the current row, and decrements the current row to the row returned. If FETCH PRIOR is the first fetch against a cursor, no row is returned and the cursor is left positioned before the first row.
- FIRST
Returns the first row in the cursor and makes it the current row.
- LAST
Returns the last row in the cursor and makes it the current row.
- ABSOLUTE { n | **@**nvar}
If n or @nvar is positive, returns the row n rows from the front of the cursor and makes the returned row the new current row. If n or @nvar is negative, returns the row n rows before the end of the cursor and makes the returned row the new current row. If n or @nvar is 0, no rows are returned. n must be an integer constant and @nvar must be smallint, tinyint, or int.
- RELATIVE { n | **@**nvar}
If n or @nvar is positive, returns the row n rows beyond the current row and makes the returned row the new current row. If n or @nvar is negative, returns the row n rows prior to the current row and makes the returned row the new current row. If n or @nvar is 0, returns the current row. If FETCH RELATIVE is specified with n or @nvar set to negative numbers or 0 on the first fetch done against a cursor, no rows are returned. n must be an integer constant and @nvar must be smallint, tinyint, or int.
- GLOBAL
Specifies that cursor_name refers to a global cursor.
- cursor_name
Is the name of the open cursor from which the fetch should be made. If both a global and a local cursor exist with cursor_name as their name, cursor_name to the global cursor if GLOBAL is specified and to the local cursor if GLOBAL is not specified.
- @cursor_variable_name
Is the name of a cursor variable referencing the open cursor from which the fetch should be made.
- INTO @variable_name[ ,...n]
Allows data from the columns of a fetch to be placed into local variables. Each variable in the list, from left to right, is associated with the corresponding column in the cursor result set. The data type of each variable must either match or be a supported implicit conversion of the data type of the corresponding result set column. The number of variables must match the number of columns in the cursor select list.
Remarks
If the SCROLL option is not specified in an SQL-92 style DECLARE CURSOR statement, NEXT is the only FETCH option supported. If SCROLL is specified in an SQL-92 style DECLARE CURSOR, all FETCH options are supported.
When the Transact-SQL DECLARE cursor extensions are used, these rules apply:
- If either FORWARD_ONLY or FAST_FORWARD is specified, NEXT is the only FETCH option supported.
- If DYNAMIC, FORWARD_ONLY or FAST_FORWARD are not specified, and one of KEYSET, STATIC, or SCROLL are specified, all FETCH options are supported.
- DYNAMIC SCROLL cursors support all the FETCH options except ABSOLUTE.
The @@FETCH_STATUS function reports the status of the last FETCH statement. The same information is recorded in the fetch_status column in the cursor returned by sp_describe_cursor. This status information should be used to determine the validity of the data returned by a FETCH statement prior to attempting any operation against that data. For more information, see @@FETCH_STATUS.
Permissions
FETCH permissions default to any valid user.
Examples
A. Use FETCH in a simple cursor
This example declares a simple cursor for the rows in the Person.Contact table with a last name beginning with B, and uses FETCH NEXT to step through the rows. The FETCH statements return the value for the column specified in the DECLARE CURSOR as a single-row result set.
USE AdventureWorks
GO
DECLARE contact_cursor CURSOR FOR
SELECT LastName FROM Person.Contact
WHERE LastName LIKE 'B%'
ORDER BY LastName
OPEN contact_cursor
-- Perform the first fetch.
FETCH NEXT FROM contact_cursor
-- Check @@FETCH_STATUS to see if there are any more rows to fetch.
WHILE @@FETCH_STATUS = 0
BEGIN
-- This is executed as long as the previous fetch succeeds.
FETCH NEXT FROM contact_cursor
END
CLOSE contact_cursor
DEALLOCATE contact_cursor
GO
B. Use FETCH to store values in variables
This example is similar to the last example, except the output of the FETCH statements is stored in local variables rather than being returned directly to the client. The PRINT statement combines the variables into a single string and returns them to the client.
USE AdventureWorks
GO
-- Declare the variables to store the values returned by FETCH.
DECLARE @LastName varchar(50), @FirstName varchar(50)
DECLARE contact_cursor CURSOR FOR
SELECT LastName, FirstName FROM Person.Contact
WHERE LastName LIKE 'B%'
ORDER BY LastName, FirstName
OPEN contact_cursor
-- Perform the first fetch and store the values in variables.
-- Note: The variables are in the same order as the columns
-- in the SELECT statement.
FETCH NEXT FROM contact_cursor
INTO @LastName, @FirstName
-- Check @@FETCH_STATUS to see if there are any more rows to fetch.
WHILE @@FETCH_STATUS = 0
BEGIN
-- Concatenate and display the current values in the variables.
PRINT 'Contact Name: ' + @FirstName + ' ' + @LastName
-- This is executed as long as the previous fetch succeeds.
FETCH NEXT FROM contact_cursor
INTO @LastName, @FirstName
END
CLOSE contact_cursor
DEALLOCATE contact_cursor
GO
C. Declare a SCROLL cursor and use the other FETCH options
This example creates a SCROLL cursor to allow full scrolling capabilities through the LAST, PRIOR, RELATIVE, and ABSOLUTE options.
USE AdventureWorks
GO
-- Execute the SELECT statement alone to show the
-- full result set that is used by the cursor.
SELECT LastName, FirstName FROM Person.Contact
ORDER BY LastName, FirstName
-- Declare the cursor.
DECLARE contact_cursor SCROLL CURSOR FOR
SELECT LastName, FirstName FROM Person.Contact
ORDER BY LastName, FirstName
OPEN contact_cursor
-- Fetch the last row in the cursor.
FETCH LAST FROM contact_cursor
-- Fetch the row immediately prior to the current row in the cursor.
FETCH PRIOR FROM contact_cursor
-- Fetch the second row in the cursor.
FETCH ABSOLUTE 2 FROM contact_cursor
-- Fetch the row that is three rows after the current row.
FETCH RELATIVE 3 FROM contact_cursor
-- Fetch the row that is two rows prior to the current row.
FETCH RELATIVE -2 FROM contact_cursor
CLOSE contact_cursor
DEALLOCATE contact_cursor
GO
See Also
Reference
CLOSE (Transact-SQL)
DEALLOCATE (Transact-SQL)
DECLARE CURSOR (Transact-SQL)
OPEN (Transact-SQL)