Updating record through cursor

[SCREENSHOT – LONG CLICK] By long pressing on record you can Delete or Update record.

We will need to create three layouts for our project Layout 1: activity_This layout holds all the records and an Add button to add records.

I didn't use any performance metric other than execution time to evaluate the results. My first test compared a single SELECT statement to a cursor to determine the count of records and the sum of the rates. As you can see both the SELECT statement and the cursor sum amounts and count the records.

My test server was an empty dual-Pentium III 450Mhz Xeon with 2GB of RAM and a 50GB RAID array. My statement selected 873 of the records in the table. They both returned the same record count and the same total.

(However, loops automatically use a cursor internally to avoid memory problems.) A more interesting usage is to return a reference to a cursor that a function has created, allowing the caller to read the rows.

This provides an efficient way to return large row sets from functions. As usual, this gives flexibility so the query plan can vary from one run to the next (see Section 39.10.2), and it also means that variable substitution is not done on the command string.

The final output should look something like following: [SCREENSHOT – FIRST SCREEN] As you can see from the screenshots above initially user will see a list (which would be empty right now, since there are no records) and button called ‘Add‘.

[SCREENSHOT – SECOND SCREEN] When user press the Add button, we’ll show him the form where user can add two fields [SCREENSHOT – FIRST SCREEN AFTER ADDING THE RECORD] By clicking the Insert button, record will be saved into SQLite database and user can see added record on the first screen.

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That's a little slower than I expected but not shocking. I assumed that a cursor could return the row once and then test the values returned to generate multiple counts.

As with is used to open a cursor variable whose query was bound to it when it was declared. A list of actual argument value expressions must appear if and only if the cursor was declared to take arguments. The query plan for a bound cursor is always considered cacheable; there is no equivalent of , as the cursor's scrolling behavior was already determined.

Argument values can be passed using either positional or named notation.

FETCH NEXT FROM cur Vendor INTO @Vendor ID, @Vendor Name END CLOSE cur Vendor DEALLOCATE cur Vendor Kalman Toth - Database, Data Warehouse & Business Intelligence Architect SQLUSA: The Best SQL Server 2005 Training in the World! Follow this pattern: SET NOCOUNT ON DECLARE @Vendor ID int, @Vendor Name nvarchar(50), @message varchar(80), @product nvarchar(50) PRINT '-------- Vendor Products Report --------' DECLARE cur Vendor CURSOR FOR SELECT Vendor ID, Name FROM Purchasing.

Vendor WHERE Preferred Vendor Status = 1 ORDER BY Vendor ID OPEN cur Vendor FETCH NEXT FROM cur Vendor INTO @Vendor ID, @Vendor Name WHILE @@FETCH_STATUS = 0 BEGIN PRINT ' ' SELECT @message = '----- Products From Vendor: ' @Vendor Name PRINT @message -- DO PROCESSING HERE -- Get the next vendor.

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