I have a few simple named queries with only joins, ant couple subselects. All of them ar working perfectly except one. The problem is, that when i run SQL code in Management Studio, i get 177 results, and when i run named query with the same SQL code, i get 20 results. I can't figure out why is that. I Call named query the as all other:
public IList<InstitutionIndexDTO> GetInstitutionIndexByWorkTimeSearch(int time, int institutionType)
{
IQuery query = GetCurrentSession()
.GetNamedQuery("GetInstitutionsListByTime")
.SetInt32("Type", institutionType)
.SetInt32("TimeUntilClose", time)
.SetResultTransformer(Transformers.AliasToBeanConstructor(typeof(InstitutionIndexDTO).GetConstructors()[0]));
return query.List<InstitutionIndexDTO>();
}
Even when i harcoded parameters in SQL, i still got the same result. I tried checking with Profiler, but generated SQL is perfect and in management studio returns all 177 results.
InstitutionIndexDTO is working correctly, because i use it with other named queries.
I have a working named query, and the one causing problems was made from that one, adding additional INNER JOIN and changing WHERE clause. Both queries returns same columns.
Maybe somebody has an idea, what i could have done wrong?
I tested my code and realised that this line is causing the problem:
(CASE WHEN (DATEPART(dw, GETDATE())) = 1 THEN 7 ELSE (DATEPART(dw, GETDATE()) - 1) END)
If i understand well, the problem is in DATEPART function. Has anybody encountered this problem?
Related
I've been attempting to increase my knowledge and trying out some challenges. I've been going at this for a solid two weeks now finished most of the challenge but this one part remains. The error is shown below, what am i not understanding?
Error in sqlite query: update users set last_browser= 'mozilla' + select sql from sqlite_master'', last_time= '13-04-2019' where id = '14'
edited for clarity:
I'm trying a CTF challenge and I'm completely new to this kind of thing so I'm learning as I go. There is a login page with test credentials we can use for obtaining many of the flags. I have obtained most of the flags and this is the last one that remains.
After I login on the webapp with the provided test credentials, the following messages appear: this link
The question for the flag is "What value is hidden in the database table secret?"
So from the previous image, I have attempted to use sql injection to obtain value. This is done by using burp suite and attempting to inject through the user-agent.
I have gone through trying to use many variants of the injection attempt shown above. Im struggling to find out where I am going wrong, especially since the second single-quote is added automatically in the query. I've gone through the sqlite documentation and examples of sql injection, but I cannot sem to understand what I am doing wrong or how to get that to work.
A subquery such as select sql from sqlite_master should be enclosed in brackets.
So you'd want
update user set last_browser= 'mozilla' + (select sql from sqlite_master''), last_time= '13-04-2019' where id = '14';
Although I don't think that will achieve what you want, which isn't clear. A simple test results in :-
You may want a concatenation of the strings, so instead of + use ||. e.g.
update user set last_browser= 'mozilla' || (select sql from sqlite_master''), last_time= '13-04-2019' where id = '14';
In which case you'd get something like :-
Thanks for everyone's input, I've worked this out.
The sql query was set up like this:
update users set last_browser= '$user-agent', last_time= '$current_date' where id = '$id_of_user'
edited user-agent with burp suite to be:
Mozilla', last_browser=(select sql from sqlite_master where type='table' limit 0,1), last_time='13-04-2019
Iterated with that found all tables and columns and flags. Rather time consuming but could not find a way to optimise.
I have encountered a strange situation in DB2 UDB V11.
When I run SELECT COUNT(*) FROM view_name it returns 0 rows.
However, when I run SELECT * FROM *view_name* the data is returned properly.
I have tried dropping and re-creating the view and ran REORG and RUNSTAT on the underlying table.
Have anyone seen this situation before?
I have seen this before when a MQT was involved. Because the optimizer will use the best way to query and can rewrite it to use the MQT this situation could happen when the MQT has not been refreshed but the table itsef has been updated/deleted already.
So check if any MQTs are involved.
I am new to robotframework and I am trying to get the hang of the keywords of DatabaseLibrary. I am getting error at 3 of such keywords.
1) I am using rowcount keywords as below-
${rowCount} Row Count <sql query>
And I always get ${rowCount}=0 irrespective of the number of rows in my table.
2) I am using Delete All Rows From Table as below-
Delete All Rows From Table <Table_Name>
And I get ORA-00911: invalid character but if use the same table with other keywords like Query ,it works fine.
3) I am using Table Must Exist as below-
Table Must Exist <Table_Name>
And I get ORA-00942: table or view does not exist but this table is very much there.
Please help me find what am I doing wrong.
Thanks in Advance!!!
I could be wrong but I believe a colleague told me there were issues, at the very least with the Row Count keyword.
However, for all three options there are easy solutions, which you've even hinted at in your question by using Query or Execute SQL Script
1)
${result}= Query Select count(id) from table
${rc} = ${result[0][0]} #Play with this as I forget exact syntax
2) Put your delete script in a test scripts folder with your tests and call it using Execute SQL script. You could also use Query to perform a select query before and after to confirm expected states.
3) Again perform a query against the table you're expecting to be there, a simple row count on id would do for this purpose. You could set a variable based on the result and use this again later if required.
I had similar issues.
I use cx_Oracle.
With the Table Must Exist keyword my problem was the same.
I dont really understand why, but first I have to use Encode String to Bytes keyword.
And I need to use a DatabaseLibrary 0.8 at least, because earlier versions didnt have solution for cx_Oracle. These solved this issue for me.
But with Delete all rows from table I still have problems.
Because this keyword puts a ; at the end of the line and it passes on that line to execute query if I understand weel, so it still causes an ORA-00911 error for me.
With Execute Sql String and the command DELETE FROM tablename you can have the same results, but it will work this way.
I hope it helps a little
I have a question on creating running totals in MS Access 2010 similar to the one here:
Access 2010 - query showing running total for multiple records, dropping old record and adding new record on each line
However when I input the equivalent code from that thread I get an error saying that the database cannot be found (Access seems to think the table I have specified is the database name)
Here is the code from the original thread:-
SELECT hbep1.EmployeeID, hbep1.PayPeriodID,
(
SELECT Sum(hbep2.HoursUsed)
FROM Hours_by_Empl_PP hbep2
WHERE hbep2.EmployeeID=hbep1.EmployeeID
AND (hbep2.PayPeriodID Between hbep1.[PayPeriodID]-3
And hbep1.[PayPeriodID])
) AS Sum_of_Hours_last_4_PPs
FROM Hours_by_Empl_PP hbep1;
Here is the code I inputted into my query:-
SELECT
V4_Try.ID_NIS_INV_HDR,
V4_Try.ID_ITM,
V4_Try.RunTot3,
V4_Try.BomVsActQty,
DMin("RunTot3","V4_Try","[ID_Itm]=" & [ID_ITM]) AS IDItmMin,
DMax("RunTot3","V4_Try","[ID_Itm]=" & [ID_ITM]) AS IDItmMax,
(
SELECT Sum([V4_Try].[BomVsActQty])
FROM [V4_Try].[BomVsActQty]
WHERE [V4_Try].[ID_ITM]=[V4_Try].[ID_ITM]
AND (IDItmMax < IDItmMin)
) AS RunTot6
FROM V4_Try
ORDER BY V4_Try.ID_ITM, V4_Try.RunTot3;
One thing I notice is that the main query uses DMax() and DMin() to create some aliased columns
...
DMin("RunTot3","V4_Try","[ID_Itm]=" & [ID_ITM]) AS IDItmMin,
DMax("RunTot3","V4_Try","[ID_Itm]=" & [ID_ITM]) AS IDItmMax,
...
and then the subquery tries to use those aliases in its WHERE clause
(
SELECT ...
WHERE...
AND (IDItmMax < IDItmMin)
) AS RunTot6
I'm pretty sure that the subquery will have no knowledge of the column aliases in the "parent" query, so they may be the items that are unrecognized.
Start by running this query:
SELECT * FROM V4_Try;
Then develop for complexity. Build the nested query before anything else. When you know that runs, try adding your aliases, then the DMax() function, and so on. Isolate the point at which you have an error popping up.
This is the process to fix a query.
Oh, and please specify the precise error that is raised by Access. Also, if this is being run from VBA, please let us know because that affects your trouble-shooting.
This question is a followup to This Question
The solution, clearing the execution plan cache seemed to work at the time, but i've been running into the same problem over and over again, and clearing the cache no longer seems to help. There must be a deeper problem here.
I've discovered that if I remove the .Distinct() from the query, it returns rows (with duplicates) in about 2 seconds. However, with the .Distinct() it takes upwards of 4 minutes to complete. There are a lot of rows in the tables, and some of the where clause fields do not have indexes. However, the number of records returned is fairly small (a few dozen at most).
The confusing part about it is that if I get the SQL generated by the Linq query, via Linqpad, then execute that code as SQL or in SQL Management Studio (including the DISTINCT) it executes in about 3 seconds.
What is the difference between the Linq query and the executed SQL?
I have a short term workaround, and that's to return the set without .Distinct() as a List, then using .Distinct on the list, this takes about 2 seconds. However, I don't like doing SQL Server work on the web server.
I want to understand WHY the Distinct is 2 orders of magnitude slower in Linq, but not SQL.
UPDATE:
When executing the code via Linq, the sql profiler shows this code, which is basically identical query.
sp_executesql N'SELECT DISTINCT [t5].[AccountGroupID], [t5].[AccountGroup]
AS [AccountGroup1]
FROM [dbo].[TransmittalDetail] AS [t0]
INNER JOIN [dbo].[TransmittalHeader] AS [t1] ON [t1].[TransmittalHeaderID] =
[t0].[TransmittalHeaderID]
INNER JOIN [dbo].[LineItem] AS [t2] ON [t2].[LineItemID] = [t0].[LineItemID]
LEFT OUTER JOIN [dbo].[AccountType] AS [t3] ON [t3].[AccountTypeID] =
[t2].[AccountTypeID]
LEFT OUTER JOIN [dbo].[AccountCategory] AS [t4] ON [t4].[AccountCategoryID] =
[t3].[AccountCategoryID]
LEFT OUTER JOIN [dbo].[AccountGroup] AS [t5] ON [t5].[AccountGroupID] =
[t4].[AccountGroupID]
LEFT OUTER JOIN [dbo].[AccountSummary] AS [t6] ON [t6].[AccountSummaryID] =
[t5].[AccountSummaryID]
WHERE ([t1].[TransmittalEntityID] = #p0) AND ([t1].[DateRangeBeginTimeID] = #p1) AND
([t1].[ScenarioID] = #p2) AND ([t6].[AccountSummaryID] = #p3)',N'#p0 int,#p1 int,
#p2 int,#p3 int',#p0=196,#p1=20100101,#p2=2,#p3=0
UPDATE:
The only difference between the queries is that Linq executes it with sp_executesql and SSMS does not, otherwise the query is identical.
UPDATE:
I have tried various Transaction Isolation levels to no avail. I've also set ARITHABORT to try to force a recompile when it executes, and no difference.
The bad plan is most likely the result of parameter sniffing: http://blogs.msdn.com/b/queryoptteam/archive/2006/03/31/565991.aspx
Unfortunately there is not really any good universal way (that I know of) to avoid that with L2S. context.ExecuteCommand("sp_recompile ...") would be an ugly but possible workaround if the query is not executed very frequently.
Changing the query around slightly to force a recompile might be another one.
Moving parts (or all) of the query into a view*, function*, or stored procedure* DB-side would be yet another workaround.
* = where you can use local params (func/proc) or optimizer hints (all three) to force a 'good' plan
Btw, have you tried to update statistics for the tables involved? SQL Server's auto update statistics doesn't always do the job, so unless you have a scheduled job to do that it might be worth considering scripting and scheduling update statistics... ...tweaking up and down the sample size as needed can also help.
There may be ways to solve the issue by adding* (or dropping*) the right indexes on the tables involved, but without knowing the underlying db schema, table size, data distribution etc that is a bit difficult to give any more specific advice on...
* = Missing and/or overlapping/redundant indexes can both lead to bad execution plans.
The SQL that Linqpad gives you may not be exactly what is being sent to the DB.
Here's what I would suggest:
Run SQL Profiler against the DB while you execute the query. Find the statement which corresponds to your query
Paste the whole statment into SSMS, and enable the "Show Actual Execution Plan" option.
Post the resulting plan here for people to dissect.
Key things to look for:
Table Scans, which usually imply that an index is missing
Wide arrows in the graphical plan, indicating lots of intermediary rows being processed.
If you're using SQL 2008, viewing the plan will often tell you if there are any indexes missing which should be added to speed up the query.
Also, are you executing against a DB which is under load from other users?
At first glance there's a lot of joins, but I can only see one thing to reduce the number right away w/out having the schema in front of me...it doesn't look like you need AccountSummary.
[t6].[AccountSummaryID] = #p3
could be
[t5].[AccountSummaryID] = #p3
Return values are from the [t5] table. [t6] is only used filter on that one parameter which looks like it is the Foreign Key from t5 to t6, so it is present in [t5]. Therefore, you can remove the join to [t6] altogether. Or am I missing something?
Are you sure you want to use LEFT OUTER JOIN here? This query looks like it should probably be using INNER JOINs, especially because you are taking the columns that are potentially NULL and then doing a distinct on it.
Check that you have the same Transaction Isolation level between your SSMS session and your application. That's the biggest culprit I've seen for large performance discrepancies between identical queries.
Also, there are different connection properties in use when you work through SSMS than when executing the query from your application or from LinqPad. Do some checks into the Connection properties of your SSMS connection and the connection from your application and you should see the differences. All other things being equal, that could be the difference. Keep in mind that you are executing the query through two different applications that can have two different configurations and could even be using two different database drivers. If the queries are the same then that would be only differences I can see.
On a side note if you are hand-crafting the SQL, you may try moving the conditions from the WHERE clause into the appropriate JOIN clauses. This actually changes how SQL Server executes the query and can produce a more efficient execution plan. I've seen cases where moving the filters from the WHERE clause into the JOINs caused SQL Server to filter the table earlier in the execution plan and significantly changed the execution time.