Software Applications Programming Errors and solutions.

SQL Server Profiler. It is a graphical based tool provided by SQL Server. It enables you to trace a query. For example.you have a SP which you wish to trace. you can execute the SP and start a profiler trace on it. It will show you row by row execution of the SP SQL Server Profiler is used to trace and analyze the SQL Server running processes and queries in the cases of performance issue. It is taken high memory so not used in main server. It is have so many events for trace. so your select desired event and filter it. It can use to find the blocking by applying trace and catch everythng runing on the server

WITH [Blocking]AS (SELECT w.[session_id] ,s.[original_login_name] ,s.[login_name] ,w.[wait_duration_ms] ,r.[scheduler_id] ,w.[wait_type] ,r.[status] ,r.[wait_resource] ,w.[resource_description] ,s.[program_name] ,w.[blocking_session_id] ,s.[host_name] ,r.[command] ,r.[percent_complete] ,r.[cpu_time] ,r.[total_elapsed_time] ,r.[reads] ,r.[writes] ,r.[logical_reads] ,r.[row_count] ,q.[text] ,q.[dbid] ,p.[query_plan] ,r.[plan_handle] FROM [sys].[dm_os_waiting_tasks] w INNER JOIN [sys].[dm_exec_sessions] s ON w.[session_id] = s.[session_id] INNER JOIN [sys].[dm_exec_requests] r ON s.[session_id] = r.[session_id] CROSS APPLY [sys].[dm_exec_sql_text](r.[plan_handle]) q CROSS APPLY [sys].[dm_exec_query_plan](r.[plan_handle]) p WHERE w.[session_id] > 50 ) Insert into Blocking_v1 ([session_id] ,[blocking_session_id] ,[WaitingUserSessionLogin] ,[BlockingUserSessionLogin] ,[scheduler_id]

1.SP_who2 shows one extra column that is RAM utilization than SP_WHO. 2.SP_who2 has these extra columns  a. CPU Time b. Disk IO c. Last Batch d. Program Name , apart from that SP_who is documented and Sp_who2 is not documented in BOL.

A covering index is a non-clustered index which includes all columns referenced in the query and therefore, the optimizer does not have to perform an additional look-up to the table in order to retrieve the data requested. As the data requested is all indexed by the covering index, it is a faster operation. covering index is a non-clustered index which stores additional columns at leaf level to avoid bookmark lookup to heap/clustered index.this is typically created using INCLUDE clause. Let say we have a table tab1 and we have columns starts from column 1 to 10. and we have clustered index on column1 and non clustered index on column 2 . for example you written a query select * from tab1 where column 2=200. this query first will go and look for the matching data in non clustered index and because of our query want to retrieve all the columns it will perform key look up , not helathy. this time i had one more non clustered index on column3 and column4 ,composite.in this case our query

SQL server assign default port 1433 to default instance...for named instance it dynamically allots a port number, ideally it is five digit port number. To see port of SQL Server you can check as below. Go to configuration manager-->SQL Serve network Configuration-> Select instance-->right click TCP/IP properties-->IP Properties

Dac means dedicared admin account, which is used to access sql server at .by default 1433 is sql server port , 1434 ia dac account. Starting the server in single user mode will use DAC (Dedicated Administrative Connection) connection. DAC Connection will use If the number of connections are limited for the instance and all are connected and if some one wants to connect and fails to troubleshoot if DBA want to connect he will also be restricted then he can use DAC connection to connect to the instance. When ever the SQL Server standard connection not establish the connection then we go with DAC connection . only sys admin can use this DAC to connect the server and troubleshoot the problems.

1.What are Differences in Delete & Truncate . 2.What are Differences in UNIQUE and Primary key ? 3. What are the agents involved in replication 4.Which Types of clusters and how many ips are required to install failover cluster? 5.Configuration of logshipping and DB mirroring. 5.What are Types of backups and backup scenario? 6.What is deadlock and blocking? 7.Differences between clustered and non clustered indexes? 8.Why SQL Server Agent is used? 9.What are Types of System databases 10.What are the steps for restoring a database?