Topic: Whether the variant at which one moment of time some flows change the data is possible?
Is WEB the server which unit is connected to basis and makes changes to the table-counter. On how many I understand at once time on web the server "heap" of requests can come, and in a flash go set of requests to basis.
There is a stored procedure, for example a script the idle time:
CREATE PROCEDURE [Test] AS UPDATE [Test_Table] SET [Inc_Fild] = [Inc_Fild] - 1 GO
For example [Inc_Fild] = 100, at once time 100 requests on web the server which which unit began to cause in hundred different flows came. If not to do BEGIN TRANSACTION, at completion of 100 requests [Inc_Fild] it will be equal "0", or is not present? I to what, whether can be a situation when, the first flow of a procedure call makes changes in a DB and the second reads as though "the dirty" data which changes did not happen yet? Or MSSQL does not allow to make it, and executions of set of flows rises in queue and there will be a performance one behind another?