Need help understanding some cursor code

I need help understanding some sql which uses Cursors. Look at lines 7 and 8 below. What is this code doing? Is it selecting the very first row of the cursor and storing it in the variables (@lchCountryCode, @lchPrefix, @lchSuffix), or is it selecting the last row? I need some help understanding this and am seeking expert help please.


1     DECLARE CURS_COUNTRY
2     FOR
3      SELECT COPAL_COUNTRY_CD, COPAL_PREFIX, COPAL_SUFFIX
4      FROM TBL_FCTS_COPAL_STATE_CDS COPAL
5      WHERE COPAL.COPAL_ACTIVE = 1
6       ORDER BY COPAL_STATE_CD


7      OPEN CUR_COUNTRY
8      FETCH NEXT FROM CURS_COUNTRY
9      INTO @lchCountryCode, @lchPrefix, @lchSuffix
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brgdotnetcontractorAsked:
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Brian CroweDatabase AdministratorCommented:
It is basically pulling the first row of the dataset into the variables.  Typically you would have an OPEN then a FETCH to pull the first row then a while loop to cycle through the remaining rows with an identical FETCH as the last action within the loop to pull the subsequent row of data.
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Vikas GargBusiness Intelligence DeveloperCommented:
Hi,

Life Cycle of Cursor

    1. Declare Cursor

     A cursor is declared by defining the SQL statement that returns a result set.
   
   2. Open

    A Cursor is opened and populated by executing the SQL statement defined by the cursor.
   
3. Fetch

    When cursor is opened, rows can be fetched from the cursor one by one or in a block to do data manipulation.
   
4. Close

After data manipulation, we should close the cursor explicitly.

5.  Deallocate

    Finally, we need to delete the cursor definition and released all the system resources associated with the cursor.

Syntax to Declare Cursor

Declare Cursor SQL Comaand is used to define the cursor with many options that impact the scalablity and loading behaviour of the cursor. The basic syntax is given below

     DECLARE cursor_name CURSOR
     [LOCAL | GLOBAL] --define cursor scope
     [FORWARD_ONLY | SCROLL] --define cursor movements (forward/backward)
     [STATIC | KEYSET | DYNAMIC | FAST_FORWARD] --basic type of cursor
     [READ_ONLY | SCROLL_LOCKS | OPTIMISTIC] --define locks
     FOR select_statement --define SQL Select statement
     FOR UPDATE [col1,col2,...coln] --define columns that need to be updated 

Syntax to Open Cursor

A Cursor can be opened locally or globally. By default it is opened locally. The basic syntax to open cursor is given below:

     OPEN [GLOBAL] cursor_name --by default it is local 

Syntax to Fetch Cursor

Fetch statement provides the many options to retrieve the rows from the cursor. NEXT is the default option. The basic syntax to fetch cursor is given below:

     FETCH [NEXT|PRIOR|FIRST|LAST|ABSOLUTE n|RELATIVE n]
    FROM [GLOBAL] cursor_name 
    INTO @Variable_name[1,2,..n] 

Syntax to Close Cursor

Close statement closed the cursor explicitly. The basic syntax to close cursor is given below:

     CLOSE cursor_name --after closing it can be reopen 

Syntax to Deallocate Cursor

Deallocate statement delete the cursor definition and free all the system resources associated with the cursor. The basic syntax to close cursor is given below:

     DEALLOCATE cursor_name --after deallocation it can't be reopen 

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