SQL is an acronym for Structured Query Language. SQL is the standard language for communicating with relational databases. Short requests, called queries, are made to an SQL-compliant database and the results are returned. The results or answers to the query usually contain the data requested. SQL is designed not only to retrieve data from a database, but also to insert and update data. SQL Tutorial and Tips

      Select | Insert | Update | Delete

      Open Cursor | Fetch

      Close Cursor | Union





        Structured Query Language
FETCH

Retrieves a specific row from the cursor.

Syntax:

FETCH [[NEXT | PRIOR | FIRST | LAST | ABSOLUTE n | RELATIVE n] FROM]
cursor_name
[INTO @variable_name1, @variable_name2, ...]
where


Note:
NEXT, PRIOR, FIRST, LAST, ABSOLUTE n, and RELATIVE n are available only with MS-SQL Server and not DB2

NEXT
Returns the first row of the results set if this is the first fetch against the cursor; otherwise, it moves the cursor one row within the results set. NEXT is the primary method used to move through a results set. NEXT is the default cursor fetch.

Note:
PRIOR, FIRST, LAST, ABSOLUTE n, and RELATIVE n are available only with cursors defined with the SCROLL option.



PRIOR
Returns the previous row within the results set.

FIRST
Moves the cursor to the first row within the results set and returns the first row.

LAST
Moves the cursor to the last row within the results set and returns the last row.

ABSOLUTE n
Returns the nth row within the results set. If n is a negative value, the returned row will be the nth row counting backward from the last row of the results set.

RELATIVE n
Returns the nth row after the currently fetched row. If n is a negative value, the returned row will be the nth row counting backward from the relative position of the cursor.

FROM cursor_name
Defines the cursor from which the fetch should be made. Multiple cursors are allowed within any session provided that each has a unique name.

INTO @variable_name1, @variable_name2, ...
Allows data returned within a fetch to be placed into local variables. Each of the variables must match the datatype. Errors will occur when the datatypes are incompatible. Implicit datatype conversions are not provided here.



A global variable, @@FETCH_STATUS, will be updated at every execution of FETCH. At a successful fetch, @@FETCH_STATUS will be set to 0. If no data was fetched because the requested cursor position exceeded the results set, -1 will be returned. If the row returned is no longer a member of the results set (for example, the row was deleted from the base table after the cursor was opened), @@FETCH_STATUS will return -2. Always use this to determine the validity of the data returned from a cursor fetch prior to attempting any operation against that data.

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