Hello to every body
I need to know about sequence of execution in a select command.
I have a sql command that use a function.some thing like:
select id, function(item)
from tbl
where conditions...
I want to know that if my function on item execute before where section or vise versa.
I try to explain it more. I want to know that sql engine fetch rows accordin to where clause and then execute my function or execute my funtion and then fetch the rows according to where clause.
If you have a document or some thing that explain about sql engine and sequence of execution please let me know.
I have a sequence problem in a package and I'm unable to figure it out: I have a control flow with some elements in this specified order: a script task -> Execute SQL task -> Data Flow. The script task is responsible for setting a value on a package variable; this same variable will then be used to decide if the Data Flow is disabled or not (there's an expression on the DataFlow). However, it looks like the variable is being tested before the script actually writes it, how can I guarantee that the DataFlow's expression is evaluated only after the script task has ended? Also, I have tried putting each component inside their own sequence container and I get the same result
When we use more that one datasets in report, how can we know which dataset will be executed first. For example if we have added 2 datasets (dataset1 and dataset2) and both of them are using stored procedures. How can we know whether dataset1 will be executed first or dataset2.
In my case I need to execute one dataset first that loads data to database tables and then want to execute second dataset that calls stored procedure that depends on table data there were filled by first dataset.
How the procedure will be called inside the trigger,whether first procedure followed by second or parallel it will execute?
CREATE TRIGGER [dbo].[InsertDatFXActualStaging] ON [dbo].[DatFXActualStaging]--change this table to DatFXActualStaging for INSERT AS BEGIN SET NOCOUNT ON;
I have one Data flow, which trasfer data into two table (Parent & Child) .
My question is : Is there a way, i can load data first into parent and then child table. because child table getting load first after that parent table loading. (Execution should be Source Parent --> Destination Parent) First , (Source Child --> Destination Child) Second. In my case its executing reverse. So i have foreign key constraints at child table , its giving foreign contraints error while running ssis package
Can any one tell me, How to define my own sequence execution at the Data flow task (Source - Destination) ?
after moving off VS debugger and into management studio to exercise our SQLCLR sp, we notice that the 2nd execution gets an error suggesting that our static SqlCommand object is getting reused from the 1st execution (of the sp under mgt studio). If this is expected behavior, we have no problem limiting our statics to only completely reusable objects but would first like to know if this is expected? Is the fact that debugger doesnt show this behavior also expected?
Hi I am slowly getting to grips with SQL Server. As a part of this, I have been attempting to work on producing more efficient queries. This post is regarding what appears to be a discrepancy between the SQL Server execution plan and the actual time taken by a query to run. My brief is to produce an attendance system for an education establishment (I presume you know I'm not an A-Level student completing a project :p ). Circa 1.5m rows per annum, testing with ~3m rows currently. College_Year could strictly be inferred from the AttDateTime however it is included as a field because it a part of just about every PK this table is ever likely to be linked to. Indexes are not fully optimised yet. Table:CREATE TABLE [dbo].[AttendanceDets] ([College_Year] [smallint] NOT NULL ,[Group_Code] [char] (12) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL ,[Student_ID] [char] (8) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL ,[Session_Date] [datetime] NOT NULL ,[Start_Time] [datetime] NOT NULL ,[Att_Code] [char] (1) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL ) ON [PRIMARY]GO CREATE CLUSTERED INDEX [IX_AltPK_Clust_AttendanceDets] ON [dbo].[AttendanceDets]([College_Year], [Group_Code], [Student_ID], [Session_Date], [Att_Code]) ON [PRIMARY]GO CREATE INDEX [All] ON [dbo].[AttendanceDets]([College_Year], [Group_Code], [Student_ID], [Session_Date], [Start_Time], [Att_Code]) ON [PRIMARY]GO CREATE INDEX [IX_AttendanceDets] ON [dbo].[AttendanceDets]([Att_Code]) ON [PRIMARY]GOALL inserts are via an overnight sproc - data comes from a third party system. Group_Code is 12 chars (no more no less), student_ID 8 chars (no more no less). I have created a simple sproc. I am using this as a benchmark against which I am testing my options. I appreciate that this sproc is an inefficient jack of all trades - it has been designed as such so I can compare its performance to more specific sprocs and possibly some dynamic SQL. Sproc:CREATE PROCEDURE [dbo].[CAMsp_Att] @College_Year AS SmallInt,@Student_ID AS VarChar(8) = '________', @Group_Code AS VarChar(12) = '____________', @Start_Date AS DateTime = '1950/01/01', @End_Date as DateTime = '2020/01/01', @Att_Code AS VarChar(1) = '_' AS IF @Start_Date = '1950/01/01'SET @Start_Date = CAST(CAST(@College_Year AS Char(4)) + '/08/31' AS DateTime) IF @End_Date = '2020/01/01'SET @End_Date = CAST(CAST(@College_Year +1 AS Char(4)) + '/07/31' AS DateTime) SELECT College_Year, Group_Code, Student_ID, Session_Date, Start_Time, Att_Code FROM dbo.AttendanceDets WHERE College_Year = @College_YearAND Group_Code LIKE @Group_CodeAND Student_ID LIKE @Student_IDAND Session_Date <= @End_DateAND Session_Date >=@Start_DateAND Att_Code LIKE @Att_CodeGOMy confusion lies with running the below script with Show Execution Plan:--SET SHOWPLAN_TEXT ON--Go DECLARE @Time as DateTime Set @Time = GetDate() select College_Year, group_code, Student_ID, Session_Date, Start_Time, Att_Code from attendanceDetswhere College_Year = 2005 AND group_code LIKE '____________' AND Student_ID LIKE '________'AND Session_Date <= '2005-11-16' AND Session_Date >= '2005-11-16' AND Att_Code LIKE '_' Print 'First query took: ' + CAST(DATEDIFF(ms, @Time, GETDATE()) AS VarCHar(5)) + ' milli-Seconds' Set @Time = GetDate() EXEC CAMsp_Att @College_Year = 2005, @Start_Date = '2005-11-16', @End_Date = '2005-11-16' Print 'Second query took: ' + CAST(DATEDIFF(ms, @Time, GETDATE()) AS VarCHar(5)) + ' milli-Seconds'GO --SET SHOWPLAN_TEXT OFF--GOThe execution plan for the first query appears miles more costly than the sproc yet it is effectively the same query with no parameters. However, my understanding is the cached plan substitutes literals for parameters anyway. In any case - the first query cost is listed as 99.52% of the batch, the sproc 0.48% (comparing the IO, cpu costs etc support this). BUT the text output is:(10639 row(s) affected) First query took: 596 milli-Seconds (10639 row(s) affected) Second query took: 2856 milli-SecondsI appreciate that logical and physical performance are not one and the same but can why is there such a huge discrepancy between the two? They are tested on a dedicated test server, and repeated running and switching the order of the queries elicits the same results. Sample data can be provided if requested but I assumed it would not shed much light. BTW - I know that additional indexes can bring the plans and execution time closer together - my question is more about the concept. If you've made it this far - many thanks.If you can enlighten me - infinite thanks.
Here's my case, I have written a stored procedure which will perform the following: 1. Grab data from a table using cursor, 2. Process data, 3. Write the result into another table
If I execute the stored procedure directly (thru VS.NET, or Query Analyser), it will run, but when I tried to execute it via a scheduled job, it fails.
I used the same record, same parameters, and the same statements to call the stored procedure.
The benefit of the actual execution plan is that you can see the actual number of rows passing through each step - compared to the estimated number of rows.But what about the "cost percentages" ?I believe I've read somewhere that these percentages is still just an estimate and is not based on the real execution.Does anyone know this and preferable have a link to something that documents it?Thanks
Hi, How can I generate a sequence No. using a simple SELECT statement.
like
declare @key set @key = 1
SELECT @key, e.name from Employee
Now I want to display name of the employee and Key value which should get incremented automatically for each employee.. Is there any way? Please help me..
i've been asked to write a sql sequence for a database i'm building but i haven't been using SQL very long and i have no idea how to write a sequence. Does anyone know anything about sql sequences?
Hi,I need little help with Ms SQL Server 2000. I would like to know how tocreate sequence or something like that. I want to have an automatic counterfor each row in one entity, so then I can do something like this:INSERT INTO table VALUES (use sequence(something), value, value, .... )Can you please help me?thxTomas
I have a SQL 2005 stored procedure to generate an email when passed parameters such as receipient, subject etc One of the paramteres passed to it is @body which is the body text of the message. I want to be able to add a couple of blank lines and then some footer information. This is working right now except I can't find the right way to add newlines into the string within the store procedure, so my footer information just tags right on after the bodytext. I have tried but that literally adds the two characters and n Can anyone advise how to generate newlien sequences in T-SQL. Regards Clive
Hi, I've a question, if I've the LSN (Log Sequence Number) of a transaction, keep with the program "Log Explorer", can I know which is the IP of the user that have do the transaction (perhaps serching in a log file of the Win 2000 Server) ? 10x, Clara
I would like to know how it is possible to create a sequence with sql server 2000 With Postgres SQL i create the sequence essai : create sequence essai START 1; but i don't know what is the sql command.
SELECT @ddo = a.DDO_DSCR_SHORT FROM dbo.DIM_DDO a JOIN dbo.Temp_ABR_HDR b ON a.DDO_ID = b.DDO WHERE b.SESSIONID = @sessid
SELECT @ay = AY FROM dbo.Temp_ABR_HDR WHERE SESSIONID = @sessid
-- set the default seq_no SELECT @seq_no = 1 -- get the max abrid. if no record return the seq_no will be 1 SELECT @seq_no = convert(integer, max(right(abrid, 4))) FROM dbo.ABR_HDR WHERE left(abrid, 7) = @ay + @ddo
-- convert @seq_no to string prefix by 0 SELECT @abrid = @ay + @ddo + right('0000' + rtrim(convert(char(4), @seq_no)), 4)
SELECT @ddo = a.DDO_DSCR_SHORT FROM dbo.DIM_DDO a JOIN dbo.Temp_ABR_HDR b ON a.DDO_ID = b.DDO WHERE b.SESSIONID = @sessid
SELECT @ay = AY FROM dbo.Temp_ABR_HDR WHERE SESSIONID = @sessid
-- set the default seq_no --SELECT @seq_no = 1 -- get the max abrid. if no record return the seq_no will be 1 --SELECT @seq_no = convert(integer, max(right(abrid, 4))) --FROM dbo.ABR_HDR --WHERE left(abrid, 7) = @ay + @ddo
-- convert @seq_no to string prefix by 0 --SELECT @abrid = @ay + @ddo + right('0000' + rtrim(convert(char(4),@seq_no)), 4)
Hi, I am migrating a project from Oracle to SQLServer and must use the same DDL. The entities have compound primary keys. In Oracle I ensure the compound key is unique by using a sequence table to generate one of the values for the compound key. Does SQL Server have sequence tabels or does anybody know a way to get it do something similar? Thanks
is it possible to generate a number sequence in a query (without using loop). I want the output to look as ------- ID ------- 1 2 3 4 5 6 7 8 9 .... upto the last number I give in the query
I am not sure about the ANSI/ISO rules on this? We have a SEQUENCE and insert it into a table.
CREATE SEQUENCE Cheque_Seq AS INTEGER START WITH 1 INCREMENT BY 1; CREATE TABLE Cheque_Book (cheque_seq INTEGER*NOT NULL PRIMARY KEY, cheque_amt DECIMAL (15,2) DEFAULT 0.00 NOT NULL);
If I do an insertion with the SEQUENCE in a transaction and then ROLLBACK the transaction, what happens to the sequence value? My thought is that the value should reset to the state it was in before the transaction (basic definition of a ROLLBACK). But it does not in the products I have looked at.
I need to create a function that will return a sequence number. The reason I need this to be a function is that I will use the function to create a view. In Oracle I would do something like this:
create sequence seq;
create or replace function f return number as l_seq number; begin select seq.nextval into l_seq from dual; return l_seq; end; /
create or replace view v as select f from dual;
Since Sql Server does not have a sequence object I have created a sequence table with a identity column and a procedure that inserts a dummy variable and returns the identity id. This works ok but to get my sequence number I must declare a variable, execute the procedure and select the return value. I need the procedure to be a function so that I can use it to create my view. Since I cannot use DML in a function and I cannot call a procedure from a function I am stuck. Do I have to create an extended procedure ? Any help is appreciated
hey all, im having some problem to do this. i have this one table, that has sequence for other table. table : tblpicksequence (this sequence is dynamic eg : Non=1, cons=2, RET=3) picktypepicksequenceitemref RET1x1 Non2x1 Cons3x1 i need to select record from other table depend on tblpicksequence sequence table : tbldetail idRETNonCons 1001 2110 3100 4 001 so base on tblpicksequence, RET=1, NOn=2, Cons=3, i need to list the record from tbldetail :- i.list all RET=1 ii.if (i) not exists list all Non=1 iii.if (ii) not exists list all Cons=3 i expect :- idRETNonConspicksequencepicktype 21101RET 31001RET
I have a table in which there is 5 column ...one with numbers like...1,2,3,4,..20...and one column is with description....and other column with other details...
Now I want to disply my results in sequence followed by 1,2,3,4,5,17,18,15,16,10,11,20 with all other columns...so can anybody suggest me what to do..?
Hello all,Iīm currently using a SQL Serve 2K. Would like to do a selectwhich returns the row number - this should not be physically stored inthe database. So for example, I would like to do a query against theCUSTOMER table and receive:* rowID || name1 Evander2 Ron3 Scoth4 JaneI donīt want to store the ID, because if I change the order byclause, the sequence may modifiy, and, for another example, having thesame set of data, I would receive:* rowID || name1 Scoth2 Ron3 Jane4 Evander could someone help me ?best regards,Evandro
