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  • MSSQL + Copy data from one server database table to the other

    - by lucky
    Hello All, I dont know how to copy table data from one server - database - table TO other sever - database - table. If it is with in the same server and different databases, i have used the following SELECT * INTO DB1..TBL1 FROM DB2..TBL1 (to copy with table structure and data) INSERT INTO DB1..TBL1(F1, F2) SELECT F1, F2 FROM DB2..TBL1 (copy only data) Now my question is copy the data from SERVER1 -- DB1-- TBL1 to SERVER2 -- DB2 --TBL2 Thanks in advance!

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  • Database Optimization techniques for amateurs.

    - by Zombies
    Can we get a list of basic optimization techniques going (anything from modeling to querying, creating indexes, views to query optimization). It would be nice to have a list of these, one technique per answer. As a hobbyist I would find this to be very useful, thanks. And for the sake of not being too vague, let's say we are using a maintstream DB such as MySQL or Oracle, and that the DB will contain 500,000-1m or so records across ~10 tables, some with foreign key contraints, all using the most typical storage engines (eg: InnoDB for MySQL). And of course, the basics such as PKs are defined as well as FK contraints.

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  • mysql join table - selecting the newest row

    - by cmancre
    Hi, I have the following two MySQL tables TABLE NAMES NAME_ID NAME 1 name1 2 name2 3 name3 TABLE STATUS STATUS_ID NAME_ID TIMESTAMP 1 1 2010-12-20 12:00 2 2 2010-12-20 10:00 3 3 2010-12-20 10:30 4 3 2010-12-20 14:00 I would like to select all info from table NAMES and add most recent correspondent TIMESTAMP column from table STATUS RESULT NAME_ID NAME TIMESTAMP 1 name1 2010-12-20 12:00 2 name2 2010-12-20 10:00 3 name3 2010-12-20 14:00 Am stuck on this one. How do I left join only on the newer timestamp?

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  • Updating counters through Hibernate

    - by at
    This is an extremely common situation, so I'm expecting a good solution. Basically we need to update counters in our tables. As an example a web page visit: Web_Page -------- Id Url Visit_Count So in hibernate, we might have this code: webPage.setVisitCount(webPage.getVisitCount()+1); The problem there is reads in mysql by default don't pay attention to transactions. So a highly trafficked webpage will have inaccurate counts. The way I'm used to doing this type of thing is simply call: update Web_Page set Visit_Count=Visit_Count+1 where Id=12345; I guess my question is, how do I do that in Hibernate? And secondly, how can I do an update like this in Hibernate which is a bit more complex? update Web_Page wp set wp.Visit_Count=(select stats.Visits from Statistics stats where stats.Web_Page_Id=wp.Id) + 1 where Id=12345;

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  • Coalesce and Case-When with To_Date not working as expected (Postgres bug?)

    - by ADTC
    I'm using Postgres 9.1. The following query does not work as expected. Coalesce should return the first non-null value. However, this query returns null (1?) instead of the date (2). select COALESCE( TO_DATE('','yyyymmdd'), --(1) TO_DATE('20130201','yyyymmdd') --(2) ); --(1) this evaluates independently to null --(2) this evaluates independently to the date, and therefore is the first non-null value What am I doing wrong? Any workaround? Edit: This may have nothing to do with Coalesce at all. I tried some experiments with Case When constructs; it turns out, Postgres has this big ugly bug where it treats TO_DATE('','yyyymmdd') as not null, even though selecting it returns null.

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  • What is the difference between check and foreign key?

    - by GigaPr
    Hi, i am quite confused about the difference between a FOREIGN KEY and CHECK constraint. they appear to me to achieve the same result. I mean I could create a table and enforce a Foreign key on another table, but i could create a CHECK to ensure the value in in another table. What is the difference and when to use the one or the other? thanks

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  • LinqtoSql Pre-compile Query problem with Count() on a group by

    - by Joe Pitz
    Have a LinqtoSql query that I now want to precompile. var unorderedc = from insp in sq.Inspections where insp.TestTimeStamp > dStartTime && insp.TestTimeStamp < dEndTime && insp.Model == "EP" && insp.TestResults != "P" group insp by new { insp.TestResults, insp.FailStep } into grp select new { FailedCount = (grp.Key.TestResults == "F" ? grp.Count() : 0), CancelCount = (grp.Key.TestResults == "C" ? grp.Count() : 0), grp.Key.TestResults, grp.Key.FailStep, PercentFailed = Convert.ToDecimal(1.0 * grp.Count() / tcount * 100) }; I have created this delegate: public static readonly Funct<SQLDataDataContext, int, string, string, DateTime, DateTime, IQueryable<CalcFailedTestResult>> GetInspData = CompiledQuery.Compile((SQLDataDataContext sq, int tcount, string strModel, string strTest, DateTime dStartTime, DateTime dEndTime, IQueryable<CalcFailedTestResult> CalcFailed) => from insp in sq.Inspections where insp.TestTimeStamp > dStartTime && insp.TestTimeStamp < dEndTime && insp.Model == strModel && insp.TestResults != strTest group insp by new { insp.TestResults, insp.FailStep } into grp select new { FailedCount = (grp.Key.TestResults == "F" ? grp.Count() : 0), CancelCount = (grp.Key.TestResults == "C" ? grp.Count() : 0), grp.Key.TestResults, grp.Key.FailStep, PercentFailed = Convert.ToDecimal(1.0 * grp.Count() / tcount * 100) }); The syntax error is on the CompileQuery.Compile() statement It appears to be related to the use of the select new {} syntax. In other pre-compiled queries I have written I have had to just use the select projection by it self. In this case I need to perform the grp.count() and the immediate if logic. I have searched SO and other references but cannot find the answer.

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  • self join table

    - by San82moon
    HI, i have a table, new_id----old_id----created_on 1234------5678------20100912 5678------3456------20100808 etc. i wrote this query, $q = "select event1.new_id, event1.old_id, event1.created_on,event2.new_id, event2.old_id, event2.created_on FROM replaced_isbns event1 JOIN replaced_isbns event2 ON event2.new_id = event1.old_id WHERE event1.new_id='$id'"; but i get result as 5678 - 1234, ie only one row, i want all rows... plz help me. Thanks, SLC

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  • User activity vs. System activity on the Index Usage Statistics report

    - by Zachary G Jensen
    I recently decided to crawl over the indexes on one of our most heavily used databases to see which were suboptimal. I generated the built-in Index Usage Statistics report from SSMS, and it's showing me a great deal of information that I'm unsure how to understand. I found an article at Carpe Datum about the report, but it doesn't tell me much more than I could assume from the column titles. In particular, the report differentiates between User activity and system activity, and I'm unsure what qualifies as each type of activity. I assume that any query that uses a given index increases the '# of user X' columns. But what increases the system columns? building statistics? Is there anything that depends on the user or role(s) of a user that's running the query?

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  • PHP timeslot booking*

    - by boyee007
    regarding of this question.. PHP Booking timeslot I tried 'GROUP BY' id_timeslot still didnt work, as its only showing the booked timeslot not available i tried that solution, but give me an error and not quite understand how to use 'coelence' table timeslot (id_timeslot integer); table doctor (id_doctor integer); table bookslot (id_bookslot, id_doctor, id_timeslot integer); insert into doctor (id_doctor) values (1 = doc_A), (2 = doc_B), (3 = doc_C); insert into TimeSlot (id_timeslot) values (1 = 10:00:00), (2 = 10:15:00), (3 = 10:30:00), (4 = 10:45:00); insert into bookslot (id_doctor,id_timeslot) values (1,1), (1,5), (2,1), (2,4), (3,1); Join mysql table $q = $mysqli->query("SELECT * FROM bookslot RIGHT JOIN timeslot ON bookslot.id_timeslot = timeslot.id_timeslot LEFT JOIN doctor ON bookslot.id_doctor = doctor.id_doctor "); echoing result and checking if it matches todays date or else set available while($r = $q->fetch_array(MYSQLI_ASSOC)) : echo '<tr>'; echo '<td align="center">' . $r['times'] . '</td>'; if($r['booked_date'] == date('Y-m-d') && $r['id_doctor'] == 1): echo '<td><a href="#available" class="booked">booked</a></td>'; else : echo '<td><a href="#" class="available">available</a></td>'; endif; if($r['booked_date'] == date('Y-m-d') && $r['id_doctor'] == 2): echo '<td><a href="#available" class="booked">booked</a></td>'; else : echo '<td><a href="#" class="available">available</a></td>'; endif; if($r['booked_date'] == date('Y-m-d') && $r['id_doctor'] == 3): echo '<td><a href="#available" class="booked">booked</a></td>'; else : echo '<td><a href="#" class="available">available</a></td>'; endif; echo '</tr>'; endwhile; result from webpage and i want the result look like: id_timeslot doc_A doc_B doc_C ---------------------------------------------- 1 booked booked booked 2 available available available 3 available available available 4 available booked available 5 booked available available Any other solution please!

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  • I can't able to edit my column name after saving

    - by Midhun M
    I create a new table of employee now I want to edit one of the column name in that table. I can edit but while saving a pop up window asks to save some text file. How may I resolve this? Is it possible to edit without creating a new table? The text file is /* Friday, August 22, 20144:32:53 PM User: Server: MIDHUN\SQLEXPRESS Database: LinQ Application: */ employee

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  • How do I execute a sql statement through a variable (dyname sql) that tries to do an insert into a variable table?

    - by Testifier
    If I do what I wanna do with a TEMPORARY TABLE, it works fine: DECLARE @CTRFR VARCHAR(MAX) SET @CTRFR = 'select blah blah blah' -- <-- very long select statement. this returns a 0 or some greater number. Please note! --> I NEED THIS NUMBER. IF EXISTS ( SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo][#CTRFRResult]') AND type IN ( N'U' ) ) DROP TABLE [dbo].[#CTRFRResult] CREATE TABLE #CTRFRResult ( CTRFRResult VARCHAR(MAX) ) SET @CTRFR = 'insert into #CTRFRResult ' + @CTRFR EXEC(@CTRFR) The above works fine. The problem is that several databases are using the same TEMP table. Therefore I need to use a VARIABLE table (instead of a temporary table). What I have below is not working because it says that the table must be declared. DECLARE @CTRFRResult TABLE ( CTRFRResult VARCHAR(MAX) ) SET @CTRFR = 'insert into @CTRFRResult ' + @CTRFR -- I think the issue is here. EXEC(@CTRFR) Setting @CTRFR to 'insert into...' is not working because I'm assuming the table name is out of scope. How would I go about mimicking the temporary table code using a variable table?

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  • it is possible to "group by" without losing the original rows?

    - by toPeerOrNotToPeer
    i have a query like this: ID | name | commentsCount 1 | mysql for dummies | 33 2 | mysql beginners guide | 22 SELECT ..., commentsCount // will return 33 for first row, 22 for second one FROM mycontents WHERE name LIKE "%mysql%" also i want to know the total of comments, of all rows: SELECT ..., SUM(commentsCount) AS commentsCountAggregate // should return 55 FROM mycontents WHERE name LIKE "%mysql%" but this one obviously returns a single row with the total. now i want to merge these two queries in one single only, because my actual query is very heavy to execute (it uses boolean full text search, substring offset search, and sadly lot more), then i don't want to execute it twice is there a way to get the total of comments without making the SELECT twice? !! custom functions are welcome !! also variable usage is welcome, i never used them...

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  • How do I specify a default value in a MS Access query?

    - by jheddings
    I have three tables similar to the following: tblInvoices: Number | Date | Customer tblInvDetails: Invoice | Quantity | Rate | Description tblPayments: Invoice | Date | Amount I have created a query called exInvDetails that adds an Amount column to tblInvDetails: SELECT tblInvDetails.*, [tblInvDetails.Quantity]*[tblInvDetails.Rate]* AS Amount FROM tblInvDetails; I then created a query exInvoices to add Total and Balance columns to tblInvoices: SELECT tblInvoices.*, (SELECT Sum(exInvDetails.Amount) FROM exInvDetails WHERE exInvDetails.Invoice = tblInvoices.Number) AS Total, (SELECT Sum(tblPayments.Amount) FROM tblPayments WHERE tblPayments.Invoice = tblInvoices.Number) AS Payments, (Total-Payments) AS Balance FROM tblInvoices; If there are no corresponding payments in tblPayments, the fields are null instead of 0. Is there a way to force the resulting query to put a 0 in this column?

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  • How to differenciate two tables

    - by Nemat
    Hi friends.... I have two tables.I want to get all records from one table that are different from the records in second table. For eg. if we have four records in first table like A,B,C,D and three records in second table thats A,B,C then the answer of query should be D. I have tried "EXCEPT" operator but it doesnt work fine.Kindly help me in writing correct query for the given problem. Any help is appreciated.... Thanks in Advance Nemat

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  • How to join by column name

    - by Daniel Vaca
    I have a table T1 such that gsdv |nsdv |esdv ------------------- 228.90 |216.41|0.00 and a table T2 such that ds |nm -------------------------- 'Non-Revenue Sales'|'ESDV' 'Gross Sales' |'GSDV' 'Net Sales' |'NSDV' How do I get the following table? ds |nm |val --------------------------------- 'Non-Revenue Sales'|'ESDV'|0.00 'Gross Sales' |'GSDV'|228.90 'Net Sales' |'NSDV'|216.41 I know that I can this by doing the following SELECT ds,nm,esdv val FROM T1,T2 WHERE nm = 'esdv' UNION SELECT ds,nm,gsdv val FROM T1,T2 WHERE nm = 'gsdv' UNION SELECT ds,nm,nsdv val FROM T1,T2 WHERE nm = 'nsdv' but I am looking for a more generic/nicer solution. I am using Sybase, but if you can think of a way to do this with other DBMS, please let me know. Thanks.

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  • MySQL Multiple "AND" Query

    - by Mark J
    I have a table with 2 columns (see below). A member can have multiple responses to a question RESPONSES --------- member_id INT response_id INT SAMPLE DATA member_id -- response_id 1 -- 3 1 -- 5 2 -- 1 2 -- 5 2 -- 9 3 -- 1 3 -- 5 3 -- 6 What I need to do is query the table for member that meet ALL response criteria. For example I need to select all members that have a response_id of 1 AND 5. I am using the following query: SELECT DISTINCT member_id FROM responses WHERE response_id = 1 AND response_id = 5. I would expect to get back member_id's 2,3. However I am getting nothing returned. I used EXPLAIN and it shows there is an error in my where query. What am I doing wrong? Also, is there a function similar to IN where all the criteria must be met in order to return true? Thanks for your help.

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  • How to use php variables (arrays) in mysql select statements?

    - by davidconn
    Hi everybody, How do you use a php variable (array) inside a mysql select statement? I am designing an auction site and currently working on a page that lets people view a list of all the current bids for an item. I want to display 3 columns: amountbid - the amount each bidder has bid for the item (held in tblbid) bidderid - the id of each bidder who has bid (found in tbluser) total_positivity_feedback - how many users have left positive feedback for the bidder (calculated from tblfeedback) To find the 'amount' and the 'bidderid' columns i pass the essayid URL parameter from the previous page. This works fine. Despite this, i can't display the total_positivity_feedback column for the various users who have made each bid. My mysql query looks like this: select tblbid.bidderid, tblbid.amount, (select count(tblfeedback.feedbackid) from tblfeedback WHERE tblfeedback.writerid = "ARRAY VARIABLE GOES HERE") AS total_positivity_feedback FROM tblbid WHERE tblbid.essayid = $essayid_bids I assume that the only way to accomplish this is to make the variable contain the bidderid's of those people who bid for that particular essay? I can't seem to work out how to do this tho?!? Many thanks for your help

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  • How can I find columns which have non-null values?

    - by aartist
    I have many columns in oracle database and some new are added with values. I like to find out which columns have values other than 0 or null. So I am looking for column names for which some sort of useful values exists at least in one row. How do I do this? Update: This sounds very close. How do I modify this to suit my needs? select column_name, nullable, num_distinct, num_nulls from all_tab_columns where table_name = 'SOME_TABLE'

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  • Problem with DB2 Over clause

    - by silent1mezzo
    I'm trying to do pagination with a very old version of DB2 and the only way I could figure out selecting a range of rows was to use the OVER command. This query provide's the correct results (the results that I want to paginate over). select MIN(REFID) as REFID, REFGROUPID from ARMS_REFERRAL where REFERRAL_ID<>'Draft' and REFERRAL_ID not like 'Demo%' group by REFGROUPID order by REFID desc Results: REFID REFGROUPID 302 242 301 241 281 221 261 201 225 142 221 161 ... ... SELECT * FROM ( SELECT row_number() OVER () AS rid, MIN(REFID) AS REFID, REFGROUPID FROM arms_referral where REFERRAL_ID<>'Draft' and REFERRAL_ID not like 'Demo%' group by REFGROUPID order by REFID desc ) AS t WHERE t.rid BETWEEN 1 and 5 Results: REFID REFGROUPID 26 12 22 11 14 8 11 7 6 4 As you can see, it does select the first five rows, but it's obviously not selecting the latest. If I add a Order By clause to the OVER() it gets closer, but still not totally correct. SELECT * FROM ( SELECT row_number() OVER (ORDER BY REFGROUPID desc) AS rid, MIN(REFID) AS REFID, REFGROUPID FROM arms_referral where REFERRAL_ID<>'Draft' and REFERRAL_ID not like 'Demo%' group by REFGROUPID order by REFID desc ) AS t WHERE t.rid BETWEEN 1 and 5 REFID REFGROUPID 302 242 301 241 281 221 261 201 221 161 It's really close but the 5th result isn't correct (actually the 6th result). How do I make this query correct so it can group by a REFGROUPID and then order by the REFID?

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  • Consolidating separate Loan, Purchase & Sales tables into one transaction table.

    - by Frank Computer
    INFORMIX-SE with ISQL 7.3: I have separate tables for Loan, Purchase & Sales transactions. Each tables rows are joined to their respective customer rows by: customer.id [serial] = loan.foreign_id [integer]; = purchase.foreign_id [integer]; = sale.foreign_id [integer]; I would like to consolidate the three tables into one table called "transaction", where a column "transaction.trx_type" [char(1)] {L=Loan, P=Purchase, S=Sale} identifies the transaction type. Is this a good idea or is it better to keep them in separate tables? Storage space is not a concern, I think it would be easier programming & user=wise to have all types of transactions under one table.

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  • An attempt to attach an auto-named database for file failed in Vb.Net

    - by user2454135
    I am Trying to connect database for first time , and I am getting this error : An attempt to attach an auto-named database for file VBTestDB.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share. and getting error on myconnect.Open() Heres my code : Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim myconnect As New SqlClient.SqlConnection myconnect.ConnectionString = "Data Source=.\SQLEXPRESS;AttachDbFilename=VBTestDB.mdf;Integrated Security=True;User Instance=True;" Dim mycommand As SqlClient.SqlCommand = New SqlClient.SqlCommand() mycommand.Connection = myconnect mycommand.CommandText = "INSERT INTO Card (CardNo,Name) VALUES (@cardno,@name)" myconnect.Open() Try mycommand.Parameters.Add("@cardno", SqlDbType.Int).Value = TextBox1.Text mycommand.Parameters.Add("@name", SqlDbType.NVarChar).Value = TextBox2.Text mycommand.ExecuteNonQuery() MsgBox("Success") Catch ex As System.Data.SqlClient.SqlException MsgBox(ex.Message) End Try myconnect.Close() End Sub

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