Sql Cursor example

USE [EUC]
GO
/****** Object:  StoredProcedure [dbo].[SP_SME_QueryAuditLog]    Script Date: 02/05/2015 15:54:16 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO

ALTER PROCEDURE [dbo].[SP_SME_QueryAuditLog]
(
    @ReferenceTable VARCHAR(50),
    @ReferenceNumber NVARCHAR(100)
)
AS
BEGIN
     DECLARE @NodeName VARCHAR(50);
    DECLARE @NodeValue NVARCHAR(500);
    DECLARE @NodePreValue NVARCHAR(500);
    DECLARE @LogId uniqueidentifier;
    DECLARE @LogXml xml;
    DECLARE @ProcessDate datetime;
    DECLARE @PreLogXml xml;
    DECLARE @OperationLog NVARCHAR(4000);
    DECLARE @FirstLogId uniqueidentifier;
    DECLARE @FirstOperationLog NVARCHAR(4000);
    DECLARE @FirstLogXml xml;
    DECLARE @Table NVARCHAR(50);
    set @Table=(case when @ReferenceTable='T_SME_CustInfo' then 'Customer Info' when @ReferenceTable='T_SME_IDExpiry' then 'ID Expiry'
                     when @ReferenceTable='T_SME_AC' then 'Account Info' when @ReferenceTable='T_SME_ParmACType' then 'Account Type'
                     when @ReferenceTable='T_SME_ParmCorpType' then 'Corporation Type' when @ReferenceTable='T_SME_ParmCountryCurrency' then 'Country Currency'
                     when @ReferenceTable='T_SME_ParmIDType' then 'ID Type'    when @ReferenceTable='T_SME_ParmMultiCountry' then 'Multiple Country Type'
                     when @ReferenceTable='T_SME_ParmSettleType' then 'Settle Type' when @ReferenceTable='T_SME_ParmSpecialZone' then 'Special Zone Type'
                     when @ReferenceTable='T_SME_ParmTranType' then 'Transaction Type' when @ReferenceTable='T_SME_ParmRMBSource' then 'RMB Source'
                     when @ReferenceTable='T_SME_ParmBOPCode' then 'BOP Code' when @ReferenceTable='T_SME_ParmFinanceManager' then 'Finance Fanager' end );
    
    SELECT TOP 1 @FirstLogId=LogId,@FirstOperationLog=OperationLog, @FirstLogXml=LogXml
    FROM T_SME_AuditLog t WHERE ReferenceTable=@ReferenceTable AND (ReferenceNumber=@ReferenceNumber or LOWER(ReferenceNumber) = LOWER(@ReferenceNumber))
    ORDER BY ProcessDate

    IF (@FirstOperationLog IS NULL OR @FirstOperationLog = '')
    BEGIN
print  @FirstLogId;
        SET @FirstOperationLog = '';
        DECLARE nodename_cursor CURSOR FOR SELECT cast(LogItem.query('fn:local-name(.)') as VARCHAR(50)) as NodeName
        FROM @FirstLogXml.nodes('/LogItem/*') AS T ( LogItem )   
        OPEN nodename_cursor   
        FETCH NEXT FROM nodename_cursor INTO @NodeName   
        WHILE @@FETCH_STATUS = 0   
        BEGIN    
            SELECT  @NodeValue = LogItem.value('(//*[local-name() = sql:variable("@NodeName")])[1]', 'nvarchar(500)')
            FROM @FirstLogXml.nodes('/LogItem') AS T ( LogItem );
            SET @FirstOperationLog = @FirstOperationLog + ' [' + @NodeName + ':] ' + @NodeValue;
            FETCH NEXT FROM nodename_cursor INTO @NodeName  
        END  
        CLOSE nodename_cursor   
        DEALLOCATE nodename_cursor  
        UPDATE T_SME_AuditLog SET OperationLog = @FirstOperationLog WHERE LogId = @FirstLogId;
    End

    DECLARE audit_cursor CURSOR FOR SELECT LogId,OperationLog,LogXml,ProcessDate
    FROM T_SME_AuditLog t WHERE ReferenceTable=@ReferenceTable AND (ReferenceNumber=@ReferenceNumber or LOWER(ReferenceNumber) = LOWER(@ReferenceNumber))
    ORDER BY ProcessDate DESC;
    OPEN audit_cursor   
    FETCH NEXT FROM audit_cursor INTO @LogId,@OperationLog,@LogXml,@ProcessDate
    WHILE @@FETCH_STATUS = 0   
    BEGIN   
        IF (@OperationLog IS NULL OR @OperationLog = '')
        BEGIN
            SET @OperationLog = '';
            SELECT TOP 1 @PreLogXml = LogXml
            FROM T_SME_AuditLog t
            WHERE ReferenceTable=@ReferenceTable AND (ReferenceNumber=@ReferenceNumber or LOWER(ReferenceNumber) = LOWER(@ReferenceNumber)) AND ProcessDate<@ProcessDate
            ORDER BY ProcessDate DESC;

            DECLARE nodename_cursor CURSOR FOR SELECT cast(LogItem.query('fn:local-name(.)') as VARCHAR(50)) as NodeName
            FROM @LogXml.nodes('/LogItem/*') AS T ( LogItem )   
            OPEN nodename_cursor   
            FETCH NEXT FROM nodename_cursor INTO @NodeName   
            WHILE @@FETCH_STATUS = 0   
            BEGIN    
                SELECT  @NodeValue = LogItem.value('(//*[local-name() = sql:variable("@NodeName")])[1]', 'nvarchar(500)')
                FROM @LogXml.nodes('/LogItem') AS T ( LogItem );
                SELECT  @NodePreValue = LogItem.value('(//*[local-name() = sql:variable("@NodeName")])[1]', 'nvarchar(500)')
                FROM @PreLogXml.nodes('/LogItem') AS T ( LogItem );
                IF (@NodePreValue IS NOT NULL AND @NodePreValue != '')
                BEGIN
                    IF (@NodeValue != @NodePreValue)
                    BEGIN
                        SET @OperationLog = @OperationLog+' ['+@NodeName + ':] '+@NodePreValue+' --> '+@NodeValue;
                     END
                END    
                ELSE
                BEGIN
                    SET @OperationLog = @OperationLog+' ['+@NodeName + ':] Empty --> '+@NodeValue;
                END
                FETCH NEXT FROM nodename_cursor INTO @NodeName  
            END  
            CLOSE nodename_cursor   
            DEALLOCATE nodename_cursor
        END
        UPDATE T_SME_AuditLog SET OperationLog = @OperationLog WHERE LogId = @LogId;
        FETCH NEXT FROM audit_cursor INTO @LogId,@OperationLog,@LogXml,@ProcessDate
    END  
    CLOSE audit_cursor;    
    DEALLOCATE audit_cursor;

    SELECT LogId, Operation, OperationStatus, OperationLog, ProcessBy, ProcessDate ,@Table as 'OperationTable'
    FROM T_SME_AuditLog t WHERE ReferenceTable=@ReferenceTable AND (ReferenceNumber=@ReferenceNumber or LOWER(ReferenceNumber) = LOWER(@ReferenceNumber))
    ORDER BY ProcessDate DESC;

END