MSSql EXECUTE AS USER WITH COOKIE resulting in a memory leak - sql

I need to use the command EXECUTE AS USER WITH COOKIE many times. After implementation, I was noticed that next calls (same) require more time for execution. To reset time execution helps only restart the SQL Server Service.
I wrote 2 simple tests multiple execution of commands:
EXECUTE AS USER WITH COOKIE
EXECUTE AS USER
Examples:
DECLARE #Loops INT SET #Loops = 1
DECLARE #CPU INT SET #CPU = ##CPU_BUSY
DECLARE #StartDate DATETIME SET #StartDate = GETDATE()
WHILE #Loops <= 3000
BEGIN
DECLARE #cookie VARBINARY(8000);
EXECUTE AS LOGIN = N'RestrictedLogin' WITH COOKIE INTO #cookie;
declare #ab varchar(MAX);
set #ab = convert(varchar(MAX), #cookie, 1);
REVERT WITH COOKIE = #cookie;
SET #Loops = #Loops + 1
END
PRINT 'ISNULL, both non-NULL'
PRINT 'Total CPU time: ' + CONVERT(varchar, ##CPU_BUSY - #CPU)
PRINT 'Total milliseconds: ' + CONVERT(varchar, DATEDIFF(ms, #StartDate, GETDATE()))
PRINT ''
and
DECLARE #Loops INT SET #Loops = 1
DECLARE #CPU INT SET #CPU = ##CPU_BUSY
DECLARE #StartDate DATETIME SET #StartDate = GETDATE()
WHILE #Loops <= 3000
BEGIN
DECLARE #cookie VARBINARY(8000);
EXECUTE AS LOGIN = N'RestrictedLogin';
set #cookie = convert(varbinary(8000), newid());
declare #ab varchar(MAX);
set #ab = convert(varchar(MAX), #cookie, 1);
REVERT;
SET #Loops = #Loops + 1
END
PRINT 'ISNULL, both non-NULL'
PRINT 'Total CPU time: ' + CONVERT(varchar, ##CPU_BUSY - #CPU)
PRINT 'Total milliseconds: ' + CONVERT(varchar, DATEDIFF(ms, #StartDate, GETDATE()))
PRINT ''
I noticed that for sqlservr process allocated more memory after each execution of EXECUTE AS USER WITH COOKIE command.
At the same time, sqlservr process's private memory not changed at all, after execution EXECUTE AS USER. And this example of code require a fewer time for execution (in some times between 3-100x).
To find the amount of private memory I have used the Performance Monitor
My question is -
How to correctly use the EXECUTE AS USER WITH COOKIE command without memory leaks and degradation time?

Related

sql server concating or replacing, which one is better (faster)

I have to generate a very long procedure every time for a reporting system, so i created a template for my procedure and replacing the parts are needed to, but i could do it with Concat or +(&)
for example:
set #query = '... and (
--#InnerQueries
)'
set #query = replace(#query,'--#InnerQueries',#otherValues)
vs
set #query += ' and exists (...)'
if(#xxx is not null)
set #query += 'and not exists (...)'
with replace approach it's more readable and maintainable for me, but for sake of optimization, what about Concat and attaching string together?
with replace: there are a lot of searching but less string creation
and with concat: lot's of string creation but no searching
so any idea?
I assume you're talking about using CONCAT or REPLACE to build an SQL then run it. If ultimately you'll process fewer than 100 REPLACEments, I'd go with that approach rather than CONCAT because it's more readable.
If however, you're talking about using concat/replace to create report output data and you will e.g. be carrying out 100 REPLACE operations per row on a million rows, I'd do the CONCAT route
update 2:
there could be something missing here:
if i change first variable :#sourceText_Replace
to a max value of 8000 character, and continue to add to it:
set #sourceText_Replace += '8000 character length'
set #sourceText_Replace +=#sourceText_Replace
set #sourceText_Replace +=#sourceText_Replace
set #sourceText_Replace +=#sourceText_Replace
set #sourceText_Replace +=#sourceText_Replace
set #sourceText_Replace +=#sourceText_Replace
set #sourceText_Replace +=#sourceText_Replace
it works fine, even if go up until: 16384017 character length
so any idea here is as good as mine
orginal answer:
to summarize (and if i didnt make any mistakes):
if you are searching in a long text, dont even think about using replace, it took seconds not milliseconds, but for concat obviously does not make any difference
in the blew code, in first try(small text), i just used variables default values and did not append to them,
but for second try(long Text) , i just append result from previous loop run
for long text, i did not bothered to run the loop more than 20 time, because it took over minutes.
smallText: set #destSmallText_Replace =
longText: set #destSmallText_Replace +=
here is the code for test:
SET NOCOUNT ON
drop table if exists #tempReplace
drop table if exists #tempConcat
create table #tempReplace
(
[txt] nvarchar(max) not null
)
create table #tempConcat
(
[txt] nvarchar(max) not null
)
declare #sourceText_Replace nvarchar(max) = 'small1 text to replace #textToBeReplaced after param text'
declare #text_Replace nvarchar(max) = #sourceText_Replace
declare #textToSearch nvarchar(max) = '#textToBeReplaced'
declare #textToReplace nvarchar(max) = 'textToBeReplaced'
declare #concat_Start nvarchar(max) = 'small1 text to replace'
declare #concat_End nvarchar(max) = 'after param text'
declare #text_Concat nvarchar(max) = #concat_Start
declare #whileCounter int =0
declare #maxCounter int = 5
declare #startTime datetime = getdate();
declare #endTime datetime = getdate();
begin
set #startTime = getDate();
while(#whileCounter <=#maxCounter)
begin
--long text
set #text_Replace += replace(#sourceText_Replace,#textToSearch,#textToReplace + convert(nvarchar(10), #whileCounter)) + #textToSearch
--small text
--set #text_Replace = replace(#sourceText_Replace,#textToSearch,#textToReplace + convert(nvarchar(10), #whileCounter)) + #textToSearch
--print #destSmallText_Replace
insert into #tempReplace values(#text_Replace)
set #whileCounter+=1
end
set #endTime = getDate();
print 'passedTime ' + Convert(nvarchar(20), DATEPART(millisecond, #endTime) - DATEPART(millisecond, #startTime))
end
begin
set #whileCounter = 0;
set #startTime = getDate();
while(#whileCounter <=#maxCounter)
begin
set #text_Concat += concat(#concat_Start,#textToReplace + convert(nvarchar(10), #whileCounter),#concat_End) + #textToSearch
--print #sourceSmallText_Concat
insert into #tempConcat values(#text_Concat)
set #whileCounter+=1
end
set #endTime = getDate();
print 'passedTime ' + Convert(nvarchar(20), DATEPART(millisecond, #endTime) - DATEPART(millisecond, #startTime))
end

Dynamic SQL to backup DB and copy to different locations based on day

We take daily backups of all DB's. There isn't enough space on the server so we copy it to a different server and also a different disk based on what day it is. i.e
Day 1 goes to \\SERVER2\E:\SqlBackups\Day1
Day 2 goes to \\SERVER2\E:\SqlBackups\Day2
Day 3 goes to \\SERVER2\E:\SqlBackups\Day3
Day 4 goes to \\SERVER2\H:\SqlBackups\Day4
Day 5 goes to \\SERVER2\H:\SqlBackups\Day5
etc
I want to use dynamic SQL and CMD but its not working, it either can't find the path or says the credentials are wrong even though the account has access to the shared drive
I've now decided to try getting the CMD to call a .bat file to do the copy but i'm not really familiar with how to do this.
I can obviously create a simple copy statement, but i do not know how to include the parameters etc
DECLARE #SQL NVARCHAR(MAX)
DECLARE #Location nvarchar(200)
DECLARE #Day int
SET #Day = DATEPART(dw, getdate())
IF #Day in (1,2,3) SET #Location =
'\\Server2\BackUps\SqlBackups\'
IF #Day in (4,5,6,7) SET #Location =
'\\Server\BackUps2\SqlBackups2\'
SET #Location = #Location + 'Day'+ cast(#Day as nvarchar(1)) + '\'
SET #Location = #Location + 'DB1.bak'
SET #SQL = 'master..xp_cmdshell ''copy /Y
F:\SqlBackups\LatestToCopyToServer2\DB1.bak ' + #location +
''''
EXEC #SQL
The System cannot find the path specified.
if i just do a select the string looks good to me ...
master..xp_cmdshell 'copy /Y F:\SqlBackups\LatestToCopyToServer2\DB1.bak
\Server2\BackUps\SqlBackups\Day5\DB1.bak'
To clarify i need assistance with the batch file and what to include :)

sp_add_jobstep in SQL Server

I have written this in SQL:
EXEC sp_add_jobstep
#job_name = N'Every 5 minutes log backup ',
#step_name = N'set T-sql command',
#subsystem = N'TSQL',
#command=N'DECLARE #fileName NVARCHAR(256) BACKUP LOG MM TO DISK =''F:\BackUp\Log\M-''' +dbo.UDF_Gregorian_To_Persian_WithDash(cast(GETDATE() as date))+'''-'''+ REPLACE(cast(isnull(convert(char(5), GETDATE(), 108),'''''') as nvarchar),''':''','''''') + '''.TRN''',
#retry_attempts = 1,
#retry_interval = 1 ;
GO
but SQL says
"Incorrect syntaxt near +" !
Please help me!
You can pass variables into EXEC or literal values but what you're not allowed to use are expressions.
So do your string concatenation as a separate step first:
declare #cmd nvarchar(max)
set #cmd = 'DECLARE #fileName NVARCHAR(256) BACKUP ... ' + dbo.UDF_Gregorian_To_Persian_WithDash(...) + ' ... '
EXEC sp_add_jobstep
#job_name = N'Every 5 minutes log backup ',
#step_name = N'set T-sql command',
#subsystem = N'TSQL',
#command=#cmd,
#retry_attempts = 1,
#retry_interval = 1 ;
A bit of a mess with those apostophes. What you want is:
DISK ='F:\BackUp\Log\M-x-y.TRN'
But by looking at the current string it would rather be:
DISK ='F:\BackUp\Log\M-'x'-'y'.'TRN'
So, I hope this will work better:
#command = N'DECLARE #fileName NVARCHAR(256) BACKUP LOG MM TO DISK = ''F:\BackUp\Log\M-' + cast(dbo.UDF_Gregorian_To_Persian_WithDash(cast(GETDATE() as date)) as nvarchar) + '-' + REPLACE(cast(isnull(convert(char(5), GETDATE(), 108),'''''') as nvarchar),''':''','''''') + '.TRN'''
A tip would be to print this line so you can see exactly how the output will be. In my example above the output will be something like:
..DISK ='F:\BackUp\Log\M-2015-04-27-08:31.TRN'
Edit:
Not sure what UDF_Gregorian_To_Persian_WithDash returns, but unless it is a nvarchar you'll need to CAST() that too (updated my example above with the cast).

Returning values from dynamic SQL by using sp_executesql with an output variable (Or) Error in appending the variable data at the end name dynamically

I just face a problem while working on a stored procedure,
My situation is as below,
I'm calling a stored procedure inside another stored procedure like for example,
EXEC [SP_ADMIN_INSERT_ITEM_STOCK_DETAILS]
#stk_tran_no = #cash_purchase_no,
#stk_tran_date = GetDate(),
#tran_type = 'Cash Purchase',
#item_code = #item_code,
#quantity = #quantity
Currently in the above code we are passing current date to the parameter #stk_tran_date.
But now I need to pass date to #stk_tran_date by fetching that from some other table like,
select #stk_tran_date = Convert(datetime,cash_purchase_date,103) from Cash_Purchase_14 where cash_purchase_no = 'GOH-9/2014'
If you observe my table name is like Cash_Purchase_14 where 14 is a dynamic value which changes every year, as this is 2014 financial year so it looks like Cash_Purchase_14, next year it will be Cash_Purchase_15.
Because of this i use to write these quires first as string then I'll execute them as shown below,
declare #SQL nvarchar(4000)
set #SQL =N' Declare #cash_purchase_date1 datetime
set #cash_purchase_date1 = (select cash_purchase_date from Cash_Purchase_'+ #Financialyearpart +' where cash_purchase_no = ''' + #cash_purchase_no + ''')
print #cash_purchase_date1'
exec executesql #SQL
But I need the value of the variable #cash_purchase_date1 outside this block like below,
EXEC [SP_ADMIN_INSERT_ITEM_STOCK_DETAILS]
#stk_tran_no = #cash_purchase_no,
#stk_tran_date = #cash_purchase_date1,
#tran_type = 'Cash Purchase',
#item_code = #item_code,
#quantity = #quantity
but it is giving an error like, "declare the variable #cash_purchase_date1"
In Other case i tried like calling the stored procedure in side the string like,
SET #SQL =' Declare #cash_purchase_date1 datetime
set #cash_purchase_date1 = (select cash_purchase_date from Cash_Purchase_'+ #Financialyearpart +' where cash_purchase_no = ' + #qt + #cash_purchase_no + #qt +')
print #cash_purchase_date1
EXEC [SP_ADMIN_INSERT_ITEM_STOCK_DETAILS]
#stk_tran_no = ' + #qt + #cash_purchase_no + #qt +',
#stk_tran_date = #cash_purchase_date1,
#tran_type = ''Cash Purchase'',
#item_code = ' + #qt + #item_code + #qt +',
#quantity = ' + #quantity
exec executesql #SQL
In this scenario the value of #cash_purchase_date1 is not replacing it simply retains the same.
Please help to get the value of the variable outside the block.
Or
How can I append the value 14 at the end of the table name dynamically using a variable.
I Tried like
Declare #cash_purchase_date1 datetime
set #cash_purchase_date1 = cash_purchase_date from Cash_Purchase_+ #Financialyearpart
I think i made the problem bit complicated while explaining. Please help me in solving the issue.
Thanks in advance.
You can return values from dynamic sql by using sp_executesql with an output variable:
declare #SQL nvarchar(4000);
declare #cash_purchase_date datetime;
set #SQL = N'select #cash_purchase_date = cash_purchase_date from Cash_Purchase_' + #Financialyearpart + ' where cash_purchase_no = ''' + #cash_purchase_no + '''';
exec sp_executesql #SQL, N'#cash_purchase_date datetime OUTPUT', #cash_purchase_date = #cash_purchase_date OUTPUT;
I think this will solve your problem.

Passing in a date variable or check if no date is passed in then use getdate()

I would like to pass in a date variable using sqlcmd and do a checking condition where if there is no date passing in, then set the variable to getdate().
Can anyone advise me on this? Thank you. Below is my sql script.( the getdate() part should be modify)
--Declare variable to store back up file location
DECLARE #DBBackupFile as nvarchar(128);
SET #DBBackupFile = N'C:\sqlbackup\MOL_POSHistory\MOL_POSHistory_backup_' + convert(varchar(12),(year(GETDATE()) * 10000) + (month(GETDATE()) * 100) + Day(GETDATE()) -4 ) + N'0201.bak';
--Retrive the Logical file name of the database from backup.
RESTORE FILELISTONLY
FROM DISK = #DBBackupFile
GO
--Make Database to single user Mode
ALTER DATABASE [MOL_POSHistory]
SET SINGLE_USER WITH
ROLLBACK IMMEDIATE
--Restore Database
DECLARE #DBBackupFile as nvarchar(128);
SET #DBBackupFile = N'C:\sqlbackup\MOL_POSHistory\MOL_POSHistory_backup_' + convert(varchar(12),(year(GETDATE()) * 10000) + (month(GETDATE()) * 100) + Day(GETDATE()) -4 ) + N'0201.bak';
USE master;
RESTORE DATABASE [MOL_POSHistory] FROM DISK = #DBBackupFile WITH FILE = 1,
MOVE N'MOL_POSHistory' TO N'D:\SQLData01\MOL_POSHistory.mdf',
MOVE N'MOL_POSHistory_log' TO N'F:\SQLLog\MOL_POSHistory.ldf',
NOUNLOAD, REPLACE, STATS = 10
--Set database to multi user mode
ALTER DATABASE [MOL_POSHistory] SET MULTI_USER
GO
You will need to call the SQLCMD like this making use of the –v parameter:
// Date format is YYYYMMDD
sqlcmd -S YOUR_SERVER -v inputDate="20010101" -i "YOUR_INPUT_FILE" -E
You can access the parameters passed in by SQLCMD (inputDate in this example) like this:
DECLARE #inputDate NVARCHAR(50)
DECLARE #date DATETIME
SET #inputDate = '$(inputDate)'
IF (LEN(ISNULL(#inputDate, '')) = 0) BEGIN
SET #date = GETDATE()
PRINT 'Using default date'
END
ELSE BEGIN
SET #date = #inputDate
PRINT 'Using varaible date'
END