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  • explain these select statements!

    - by user329820
    Hi, I can not get the difference betwwn these statements? would you please help me,I have read some sample of select statements but I did not get these ones. SELECT 'B' FROM T WHERE A = (SELECT NULL); SELECT 'C' FROM T WHERE A = ANY (SELECT NULL); SELECT 'D' FROM T WHERE A = A; I use MySQL

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  • Alternative to NOT EXISTS

    - by Dave Colwell
    Hi all, I have two tables linked by an ID column, lets call them Table A and table B. My goal is to find all the records in table A that have no record in table B. For instance: Table A: ID----Value 1-----value1 2-----value2 3-----value3 4-----value4 Table B ID----Value 1-----x 2-----y 4-----z 4-----l As you can see, record with ID = 3 does not exist in table B, so i want a query that will give me record 3 from table A. the way i am currently doing this is by saying AND NOT EXISTS (SELECT ID FROM TableB) but since the tables are huge, the performance on this is terrible. Also, when i tried using a Left Join where TableB.ID is null, it didnt work. Can anyone suggest an alternative?

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  • Simple ASP function question

    - by J Harley
    Good Morning, I have got the following function: FUNCTION queryDatabaseCount(sqlStr) SET queryDatabaseCountRecordSet = databaseConnection.Execute(sqlStr) If queryDatabaseCountRecordSet.EOF Then queryDatabaseCountRecordSet.Close queryDatabaseCount = 0 Else QueryArray = queryDatabaseCountRecordSet.GetRows queryDatabaseCountRecordSet.Close queryDatabaseCount = UBound(QueryArray,2) + 1 End If END FUNCTION And the following dbConnect: SET databaseConnection = Server.CreateObject("ADODB.Connection") databaseConnection.Open "Provider=SQLOLEDB; Data Source ="&dataSource&"; Initial Catalog ="&initialCatalog&"; User Id ="&userID&"; Password="&password&"" But for some reason I get the following error: ADODB.Recordset error '800a0e78' Operation is not allowed when the object is closed. /UBS/DBMS/includes/blocks/block_databaseoverview.asp, line 30 Does anyone have any suggestions? Many Thanks, Joel

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  • Listing issue, GROUP mysql

    - by SethCodes
    Here is a mock-up example of Mysql table: | ID | Country | City | ________________________________ | 1 | Sweden | Stockholm | | 2 | Sweden | Stockholm | | 3 | Sweden | Lund | | 4 | Sweden | Lund | | 5 | Germany | Berlin | | 6 | Germany | Berlin | | 7 | Germany | Hamburg | | 8 | Germany | Hamburg | Notice how both rows Country and city have repeated values inside them. Using GROUP BY country, city in my PDO query, the values will not repeat while in loop. Here is PDO for this: $query = "SELECT id, city, country FROM table GROUP BY country, city"; $stmt = $db->query($query); while($row = $stmt->fetch(PDO::FETCH_ASSOC)) : The above code will result in an output like this (some editing in-between). GROUP BY works but the country repeats: Sweden - Stockholm Sweden - Lund Germany - Berlin Germany - Hamburg Using bootstrap collapse and above code, I separate the country from the city with a simple drop down collopase. Here is code: <li> <a data-toggle="collapse" data-target="#<?= $row['id']; ?>" href="search.php?country=<?= $row['country']; ?>"> <?= $row['country']; ?> </a> <div id ="<?= $row['id']; ?>" class="collapse in"> //collapse div here <a href="search.php?city=<?= $row['city']; ?>"> <?= $row['city']; ?><br></a> </div> //end </li> It then looks something like this (once collapse is initiated): Sweden > Stockholm Sweden > Lund Germany >Berlin Germany >Hamburg Here is where I face the problem. The above lists the values Sweden and Germany 2 times. I want Sweden and Germany to only list one time, and the cities listed below, so the desired look is to be this: Sweden // Lists one time > Stockholm > Lund Germany // Lists one time >Berlin >Hamburg I have tried using DISTINCT, GROUP_CONTACT and other methods, yet none get my desired output (above). Suggestions? Below is my current full code in action: <? $query = "SELECT id, city, country FROM table GROUP BY country, city"; $stmt = $db->query($query); while($row = $stmt->fetch(PDO::FETCH_ASSOC)) : ?> <li> <a data-toggle="collapse" data-target="#<?= $row['id']; ?>" href="search.php?country=<?= $row['country']; ?>"> <?= $row['country']; ?> </a> <div id ="<?= $row['id']; ?>" class="collapse in"> //collapse div here <a href="search.php?city=<?= $row['city']; ?>"> <?= $row['city']; ?><br></a> </div> //end </li> <? endwhile ?>

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  • How Optimize sql query make it faster

    - by user502083
    Hello every one : I have a very simple small database, 2 of tables are: Node (Node_ID, Node_name, Node_Date) : Node_ID is primary key Citation (Origin_Id, Target_Id) : PRIMARY KEY (Origin_Id, Target_Id) each is FK in Node Now I write a query that first find all citations that their Origin_Id has a specific date and then I want to know what are the target dates of these records. I'm using sqlite in python the Node table has 3000 record and Citation has 9000 records, and my query is like this in a function: def cited_years_list(self, date): c=self.cur try: c.execute("""select n.Node_Date,count(*) from Node n INNER JOIN (select c.Origin_Id AS Origin_Id, c.Target_Id AS Target_Id, n.Node_Date AS Date from CITATION c INNER JOIN NODE n ON c.Origin_Id=n.Node_Id where CAST(n.Node_Date as INT)={0}) VW ON VW.Target_Id=n.Node_Id GROUP BY n.Node_Date;""".format(date)) cited_years=c.fetchall() self.conn.commit() print('Cited Years are : \n ',str(cited_years)) except Exception as e: print('Cited Years retrival failed ',e) return cited_years Then I call this function for some specific years, But it's crazy slowwwwwwwww :( (around 1 min for a specific year) Although my query works fine, it is slow. would you please give me a suggestion to make it faster? I'd appreciate any idea about optimizing this query :) I also should mention that I have indices on Origin_Id and Target_Id, so the inner join should be pretty fast, but it's not!!!

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  • Union All Won't work in stored procedure

    - by MyHeadHurts
    ALTER PROCEDURE [dbo].[MyStoredProcedure1] @YearToGet int AS Select Division, SDESCR, DYYYY, Sum(APRICE) ASofSales, Sum(PARTY) AS ASofPAX, Sum(NetAmount) ASofNetSales, Sum(InsAmount) ASofInsSales, Sum(CancelRevenue) ASofCXSales, Sum(OtherAmount) ASofOtherSales, Sum(CXVALUE) ASofCXValue From dbo.B101BookingsDetails Where Booked <= CONVERT(int,DateAdd(year, @YearToGet - Year(getdate()), DateAdd(day, DateDiff(day, 1, getdate()), 0) ) ) and (DYYYY = @YearToGet) Group By SDESCR, DYYYY, Division Having (DYYYY = @YearToGet) Order By Division, SDESCR, DYYYY union all SELECT DIVISION, SDESCR, DYYYY, SUM(APRICE) AS YESales, SUM(PARTY) AS YEPAX, SUM(NetAmount) AS YENetSales, SUM(InsAmount) AS YEInsSales, SUM(CancelRevenue) AS YECXSales, SUM(OtherAmount) AS YEOtherSales, SUM(CXVALUE) AS YECXValue FROM dbo.B101BookingsDetails Where (DYYYY=@YearToGet) GROUP BY SDESCR, DYYYY, DIVISION ORDER BY DIVISION, SDESCR, DYYYY The error I am getting is Msg 156, Level 15, State 1, Procedure MyStoredProcedure1, Line 36 Incorrect syntax near the keyword 'union'. But my goal here is the user inputs a year for example 2009, my first query will get all the sales made in 2009 to the same date it is was yesterday 12/23/2009, while the second query is getting 2009 totals up to dec 31 2009. I want the columns to be side by side not in one column

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  • Temporary intermediate table

    - by user289429
    In our project to generate massive reports in oracle we use some permanent table to hold intermediate results. For example to generate one report we run few queries and populate the table, at the final step we join the intermediate table with huge application tables. These intermediate tables are cleared for next report run. We have few concerns in performance areas. These intermediate tables are transactional and don't have statistics. Is it good idea to join these with application tables which are partitioned and have up to date statistics. We need these results stored in the intermediate tables to be available across requests from UI hence we are not in a position to use oracle provided temporary tables. Any thoughts on what could be done would be appreciated.

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  • Data historian queries

    - by Scott Dennis
    Hi, I have a table that contains data for electric motors the format is: DATE(DateTime) | TagName(VarChar(50) | Val(Float) | 2009-11-03 17:44:13.000 | Motor_1 | 123.45 2009-11-04 17:44:13.000 | Motor_1 | 124.45 2009-11-05 17:44:13.000 | Motor_1 | 125.45 2009-11-03 17:44:13.000 | Motor_2 | 223.45 2009-11-04 17:44:13.000 | Motor_2 | 224.45 Data for each motor is inserted daily, so there would be 31 Motor_1s and 31 Motor_2s etc. We do this so we can trend it on our control system displays. I am using views to extract last months max val and last months min val. Same for this months data. Then I join the two and calculate the difference to get the actual run hours for that month. The "Val" is a nonresetable Accumulation from a PLC(Controller). This is my query for Last months Max Value: SELECT TagName, Val AS Hours FROM dbo.All_Data_From_Last_Mon AS cur WHERE (NOT EXISTS (SELECT TagName, Val FROM dbo.All_Data_From_Last_Mon AS high WHERE (TagName = cur.TagName) AND (Val > cur.Val))) This is my query for Last months Max Value: SELECT TagName, Val AS Hours FROM dbo.All_Data_From_Last_Mon AS cur WHERE (NOT EXISTS (SELECT TagName, Val FROM dbo.All_Data_From_Last_Mon AS high WHERE (TagName = cur.TagName) AND (Val < cur.Val))) This is the query that calculates the difference and runs a bit slow: SELECT dbo.Motors_Last_Mon_Max.TagName, STR(dbo.Motors_Last_Mon_Max.Hours - dbo.Motors_Last_Mon_Min.Hours, 12, 2) AS Hours FROM dbo.Motors_Last_Mon_Min RIGHT OUTER JOIN dbo.Motors_Last_Mon_Max ON dbo.Motors_Last_Mon_Min.TagName = dbo.Motors_Last_Mon_Max.TagName I know there is a better way. Ultimately I just need last months total and this months total. Any help would be appreciated. Thanks in advance

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  • Find Date From Non Contiguous Ranges

    - by AGoodDisplayName
    I am looking to find an best way to find a date from date ranges that may or may not be contiguous (I am trying to avoid a cursor, or a heavy function if possible). Lets say I have hotel guests that come and go (check in, check out). I want to find the date that a certain guest stayed their 45th night with us. The database we use records the data as so: Create Table #GuestLog( ClientId int, StartDate DateTime, EndDate DateTime) Here is some data Insert Into #GuestLog Values(1, '01/01/2010', '01/10/2010') Insert Into #GuestLog Values(1, '01/16/2010', '01/29/2010') Insert Into #GuestLog Values(1, '02/13/2010', '02/26/2010') Insert Into #GuestLog Values(1, '04/05/2010', '06/01/2010') Insert Into #GuestLog Values(1, '07/01/2010', '07/21/2010') So far I can only think of solutions that involve functions with temp tables and crazy stuff like that, I feel like I'm over thinking it. Thanks ahead of time.

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  • Want to develop for Android. Have a few basic, non-FAQ questions

    - by Troy M
    Hi everyone, Recently myself and a small group of friends became interested in developing a game for a mobile platform. Originally we considered the iPhone but none of us use macs, so we decided Android would be a more realistic platform to use. Before we get started, I was hoping that I might find some answers to a couple questions so we don't waste our time if this project isn't feasible. Any help is appreciated! I can't seem to find out how many programming languages Android supports. Java is obvious, but what about C+? It seems that Android supports C and C++ through Eclipse, but is that it? (I'm not the programmer for the project which is why I'm asking this. He's comfortable in C+). Our game involves the use of two digital analog sticks (it's not a twin-stick shooter but it's a similar concept). It would seem that most Droid devices unfortunately don't use multi-touch though... Are there many devices out there right now which support this functionality and I'm just not seeing them, or should we possibly consider the development of a different game that would only use a single input? Assuming there's no snags following those first two questions, what would you consider the best screen resolution to develop in? It seems like there are a variety of resolutions out there right now and we can't decide which is the best to use. Again, any answers are appreciated!

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  • Database Design Question: GUID + Natural Numbers

    - by Alan
    For a database I'm building, I've decided to use natural numbers as the primary key. I'm aware of the advantages that GUID's allow, but looking at the data, the bulk of row's data were GUID keys. I want to generate XML records from the database data, and one problem with natural numbers is that I don't want to expose my database key's to the outside world, and allow users to guess "keys." I believe GUID's solve this problem. So, I think the solution is to generate a sparse, unique iD derived from the natural ID (hopefully it would be 2-way), or just add an extra column in the database and store a guid (or some other multibyte id) The derived value is nicer because there is no storage penalty, but it would be easier to reverse and guess compared to a GUID. I'm (buy) curious as to what others on SO have done, and what insights they have.

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  • SQLException: incorrect syntax near '2'.

    - by Tobechukwu Ezenachukwu
    whenever I call the "ExecuteNonQuery" command on the following CommandText, I get the above SQLException myCommand.CommandText = "INSERT INTO fixtures (round_id, matchcode, date_utc, time_utc, date_london, time_london, team_A_id, team_A, team_A_country, team_B_id, team_B, team_B_country, status, gameweek, winner, fs_A, fs_B, hts_A, hts_B, ets_A, ets_B, ps_A, ps_B, last_updated) VALUES (" _ & round_id & "," & match_id & "," & date_utc & ",'" & time_utc & "'," & date_london & ",'" & time_london & "'," & team_A_id & ",'" & team_A_name & "','" & team_A_country & "'," & team_B_id & ",'" & team_B_name & "','" & _ team_B_country & "','" & status & "'," & gameweek & ",'" & winner & "'," & fs_A & "," & fs_B & "," & hts_A & "," & hts_B & "," & ets_A & "," & ets_B & "," & ps_A & "," & ps_B & "," & last_updated & ")" But whenever, i remove the last table item - "last_updated", the error disappears. Please help me resolve this issue. Is there any special treatment to be given to datetime fields??? Thanks for your help

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  • Service Broker not working after database restore

    - by roryok
    Have a working Service Broker set up on a server, we're in the process of moving to a new server but I can't seem to get Service Broker set up on the new box. Have done the obvious (to me) things like Enabling Broker on the DB, dropping the route, services, contract, queues and even message type and re adding them, setting ALTER QUEUE with STATUS ON SELECT * FROM sys.service_queues gives me a list of the queues, including my own two, which show as activation_enabled, receive_enabled etc. Needless to say the queues aren't working. When I drop messages into them nothing goes in and nothing comes out. Any ideas? I'm sure there's something really obvious I've missed...

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  • advanced select in Stored Procedure

    - by Auro
    Hey i got this Table: CREATE TABLE Test_Table ( old_val VARCHAR2(3), new_val VARCHAR2(3), Updflag NUMBER, WorkNo NUMBER ); and this is in my Table: INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('1',' 20',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('2',' 20',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('2',' 30',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('3',' 30',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('4',' 40',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('4',' 40',0,0); now my Table Looks like this: Row Old_val New_val Updflag WorkNo 1 '1' ' 20' 0 0 2 '2' ' 20' 0 0 3 '2' ' 30' 0 0 4 '3' ' 30' 0 0 5 '4' ' 40' 0 0 6 '5' ' 40' 0 0 (if the value in the new_val column are same then they are together and the same goes to old_val) so in the example above row 1-4 are together and row 5-6 at the moment i have in my Stored Procedure a cursor: SELECT t1.Old_val, t1.New_val, t1.updflag, t1.WorkNo FROM Test_Table t1 WHERE t1.New_val = ( SELECT t2.New_val FROM Test_Table t2 WHERE t2.Updflag = 0 AND t2.Worknr = 0 AND ROWNUM = 1 ) the output is this: Row Old_val New_val Updflag WorkNo 1 1 20 0 0 2 2 20 0 0 my Problem is, i dont know how to get row 1 to 4 with one select. (i had an idea with 4 sub-querys but this wont work if its more data that matches together) does anyone of you have an idea?

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  • Does anybody have any suggestions on which of these two approaches is better for large delete?

    - by RPS
    Approach #1: DECLARE @count int SET @count = 2000 DECLARE @rowcount int SET @rowcount = @count WHILE @rowcount = @count BEGIN DELETE TOP (@count) FROM ProductOrderInfo WHERE ProductId = @product_id AND bCopied = 1 AND FileNameCRC = @localNameCrc SELECT @rowcount = @@ROWCOUNT WAITFOR DELAY '000:00:00.400' Approach #2: DECLARE @count int SET @count = 2000 DECLARE @rowcount int SET @rowcount = @count WHILE @rowcount = @count BEGIN DELETE FROM ProductOrderInfo WHERE ProductId = @product_id AND FileNameCRC IN ( SELECT TOP(@count) FileNameCRC FROM ProductOrderInfo WITH (NOLOCK) WHERE bCopied = 1 AND FileNameCRC = @localNameCrc ) SELECT @rowcount = @@ROWCOUNT WAITFOR DELAY '000:00:00.400' END

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  • Need a Count, but Multiple other fields

    - by user3727752
    I have a table that looks like this: person trip_id date home destination joe 1 3/10 chicago new york joe 2 4/10 chicago l.a. joe 3 5/10 chicago boston luther 4 3/12 new york chicago luther 5 3/18 new york boston I want to get a result like person trips firstDate home joe 3 3/10 chicago luther 2 3/12 new york Currently I've got Select person, count(trip_id) as trips, min(date) as firstDate from [table] group by person order by firstDate I can't figure out how to get home in there as well. Home is always unique to the person. But my DBMS doesn't know that. Is there an easy way around this problem? Appreciate it.

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  • about Select statement !

    - by user329820
    hi, I have read that after select we use column-names but I have found a statement that was like this: SELECT 'A' FROM T WHERE A = NULL; would you lease help me? thanks (A is a column- name here?) my DBMS is MySQL

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  • kohana quotes in query.

    - by peter
    hey, i want to format a date in mysql using DATE_FORMAT(tblnews.datead, '%M %e, %Y, %l:%i%p') i cant seem to get the quotes right , so i keep getting errors. how would you put this in a query?

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