Question

I have three tables and three stored procedures respectively to insert/update records in these tables. The first table has a primary key column, RecNo, which is auto-generated.

Around 1000 users are entering records in these tables simultaneously from different geographic locations. I am noticing that sometimes inserts in the second or third table get missed even when inserts were successfully done and no warning was generated.

I want to know how the auto-generated primary key column handles concurrent issues. Do I need to set isolation level to SERIALIZABLE on top of each stored procedure?

I am using SQL Server 2008 R2 Express with default isolation level, i.e., READ COMMITTED.

One of my stored procedure looks like:

ALTER PROCEDURE [dbo].[pheSch_CreateOrUpdateTubewellDetails]
    -- Add the parameters for the stored procedure here
    @TwTaskFlag nvarchar(6),
    @TwParameterID bigint,
    @SerialNumber bigint,
    @TotalNum int,
    @TwType nvarchar(50),
    @Depth nvarchar(60),
    @Diameter nvarchar(60),
    @WaterCapacity nvarchar(60),
    @PS nvarchar(15),
    @PSNum int,
    @PSType nvarchar(60),
    @Remarks nvarchar(80)
AS
BEGIN
    -- SET NOCOUNT ON added to prevent extra result sets from
    -- interfering with SELECT statements.
    SET NOCOUNT ON;

    -- Insert statements for procedure here
        BEGIN
            UPDATE tw_details
                SET 
                    TotalNum = @TotalNum,
                    TwType = @TwType,
                    Depth = @Depth,
                    Diameter = @Diameter,
                    WaterCapacity = @WaterCapacity,
                    PS = @PS,
                    PSNum = @PSNum,
                    PSType = @PSType,
                    Remarks = @Remarks
                WHERE twpid = @TwParameterID;
        END
END

Answer 1

You need not change the isolation level,
the Identity column is well suited for concurrent inserts.

IF

you have no any Triggers attached to the table – then show all the details

BUT

you noticed the INSERTS – i do not see any of them here