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  • Equivalent of Switch Statement in MySql 5

    - by Robert Gowland
    Using MySql 5, I have a task where I need to update one table based on the contents of another table. For example, I need to add 'A1' to table 'A' if table 'B' contains 'B1'. I need to add 'A2a' and 'A2b' to table 'A' if table 'B' contains 'B2', etc.. In our case, the value in table 'B' we're interested is an enum. Right now I have a stored procedure containing a series of statements like: INSERT INTO A SELECT 'A1' FROM B WHERE B.Value = 'B1'; --Repeat for 'B2' -> 'A2a', 'A2b'; 'B3' -> 'A3', etc... Is there a nicer more DRY way of accomplishing this?

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  • INSERT data from Textbox to Postgres SQL

    - by user1479013
    I just learn how to connect C# and PostgresSQL. I want to INSERT data from tb1(Textbox) and tb2 to database. But I don't know how to code My previous code is SELECT from database. this is my code private void button1_Click(object sender, EventArgs e) { bool blnfound = false; NpgsqlConnection conn = new NpgsqlConnection("Server=127.0.0.1;Port=5432;User Id=postgres;Password=admin123;Database=Login"); conn.Open(); NpgsqlCommand cmd = new NpgsqlCommand("SELECT * FROM login WHERE name='" + tb1.Text + "' and password = '" + tb2.Text + "'",conn); NpgsqlDataReader dr = cmd.ExecuteReader(); if (dr.Read()) { blnfound = true; Form2 f5 = new Form2(); f5.Show(); this.Hide(); } if (blnfound == false) { MessageBox.Show("Name or password is incorrect", "Message Box", MessageBoxButtons.OK, MessageBoxIcon.Exclamation, MessageBoxDefaultButton.Button1); dr.Close(); conn.Close(); } } So please help me the code.

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  • SaaS Multi-tenancy Applications: How is data import/export/backup being implemented?

    - by Mark Redman
    How are applications providing import / export (or backups) of data in SaaS based multi-tenancy applications, particularly single database designs? Imports: Keeping things simple I think basic imports are useful, ie CSV to a spec (or a way of providing a mapping between CSV columns and fields in the database. Exports: In single database designs I have seen XML exports and HTML (basic sitse generated) exports of data? I would assume that XML is a better option? How does one cater for relational data? Would you reference various things within XML and provide documentation of the relationships or let users figurethis out? Are vendors providing an export/backup that can be imported back in/restored? Your comments appreciated.

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  • Why MSSQL keeps throwing me Exceptions?

    - by Augusto Càzares
    I have my project in .NET that uses a db in MSSQL Server,i'm using LINQ , sometimes when the projec throws me an exception (Constraint) in a part of the project this same error keeps showing in other part of the project when i do another thing with the db, like when i do an insertion and i had before an exception on delete the insertion throws me the delete exeption, and it remainds this way until i close and open again the project, my major problem is when this happen in my online project, this error in my project causes me problems in the project i'm testing online (i use the same db). I don't know if this exception is on the memory or something but its have been causing me a lot of headechs.

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  • MySQL Delete from 1 table, using multiple tables

    - by nute
    I would like to delete all the rows found by that query: SELECT cart_abandon.* FROM cart_abandon, cart_product, txn_product, users WHERE cart_abandon.cartid = cart_product.cartid AND cart_product.productid = txn_product.productid AND txn_product.username = users.username AND users.id = cart_abandon.userid AND txn_product.txndate >= cart_abandon.abandondate The thing to keep in mind is that the query here uses 4 different tables, however I only want to delete rows from 1 table (cart_abandon). Is there an easy way to do that? Maybe this: ? DELETE cart_abandon FROM cart_abandon, cart_product, txn_product, users WHERE cart_abandon.cartid = cart_product.cartid AND cart_product.productid = txn_product.productid AND txn_product.username = users.username AND users.id = cart_abandon.userid AND txn_product.txndate >= cart_abandon.abandondate Is that valid? Correct?

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  • When should we use Views, Temporary Tables and Direct Queries ? What are the Performance issues in a

    - by Shantanu Gupta
    I want to know the performance of using Views, Temp Tables and Direct Queries Usage in a Stored Procedure. I have a table that gets created every time when a trigger gets fired. I know this trigger will be fired very rare and only once at the time of setup. Now I have to use that created table from triggers at many places for fetching data and I confirms it that no one make any changes in that table. i.e ReadOnly Table. I have to use this tables data along with multiple tables to join and fetch result for further queries say select * from triggertable By Using temp table select ... into #tx from triggertable join t2 join t3 and so on select a,b, c from #tx --do something select d,e,f from #tx ---do somethign --and so on --around 6-7 queries in a row in a stored procedure. By Using Views create view viewname ( select ... from triggertable join t2 join t3 and so on ) select a,b, c from viewname --do something select d,e,f from viewname ---do somethign --and so on --around 6-7 queries in a row in a stored procedure. This View can be used in other places as well. So I will be creating at database rather than at sp By Using Direct Query select a,b, c from select ... into #tx from triggertable join t2 join t3 join ... --do something select a,b, c from select ... into #tx from triggertable join t2 join t3 join ... --do something . . --and so on --around 6-7 queries in a row in a stored procedure. Now I can create a view/temporary table/ directly query usage in all upcoming queries. What would be the best to use in this case.

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  • C# Dataset Dynamically Add DataColumn

    - by Wesley
    I am trying to add a extra column to a dataset after a query has completed. I have a database relationship of the following: Employees / \ Groups EmployeeGroups Empoyees holds all the data for that individual, I'll name the unique key the UserID. Groups holds all the groups that a employee can be a part of, i.e. Super User, Admin, User; etc. I will name the unique key GroupID EmployeeGroups holds all the associations of which groups each employee belongs too. (UserID | GroupID) What I am trying to accomplish is after querying for a all users I want to loop though each user and add what groups that user is a part of by adding a new column to the dataset named 'Groups' which is a string to insert the values of the next query to get all the groups that user is a part of. Then by user of databinding populate a listview with all employees and their group associations My code is as follows; Position 5 is the new column I am trying to add to the dataset. string theQuery = "select UserID, FirstName, LastName, EmployeeID, Active from Employees"; DataSet theEmployeeSet = itsDatabase.runQuery(theQuery); DataColumn theCol = new DataColumn("Groups", typeof(string)); theEmployeeSet.Tables[0].Columns.Add(theCol); foreach (DataRow theRow in theEmployeeSet.Tables[0].Rows) { theRow.ItemArray[5] = "1234"; } At the moment, the code will create the new column but when i assign the data to that column nothing will be assigned, what am I missing? If there is any further explination or information I can provide, please let me know. Thank you all

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  • batch update mysql table

    - by Yang
    I have a table with a column called time, "HH:MM:SS". How can I do a batch update so that the value increment by 1 hour? Is it something like: update <table_name> set <time_column> = <time_column> + 3600 where ...

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  • SQL select all items of an owner from an item-to-owner table

    - by kdobrev
    I have a table bike_to_owner. I would like to select current items owned by a specific user. Table structure is CREATE TABLE IF NOT EXISTS `bike_to_owner` ( `bike_id` int(10) unsigned NOT NULL, `user_id` int(10) unsigned NOT NULL, `last_change_date` date NOT NULL, PRIMARY KEY (`bike_id`,`user_id`,`last_change_date`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci; In the profile page of the user I would like to display all his/her current possessions. I wrote this statement: SELECT `bike_id`,`user_id`,max(last_change_date) FROM `bike_to_owner` WHERE `user_id` = 3 group by `last_change_date` but i'm not quite sure it works correctly in all cases. Can you please verify this is correct and if not suggest me something better. Using php/mysql. Thanks in advance!

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  • how do i update database using ADODB.Recordset?

    - by every_answer_gets_a_point
    i am using excel to connect to a mysql database: Dim dpath, atime, rtime, lcalib, aname, rname, bstate, instrument As String Dim rs As ADODB.Recordset Set rs = New ADODB.Recordset ConnectDB With wsBooks rs.Open "batchinfo", oConn, adOpenKeyset, adLockOptimistic, adCmdTable Worksheets.Item("Report 1").Select dpath = Trim(Range("B2").Text) atime = Trim(Range("B3").Text) rtime = Trim(Range("B4").Text) lcalib = Trim(Range("B5").Text) aname = Trim(Range("B6").Text) rname = Trim(Range("B7").Text) bstate = Trim(Range("B8").Text) ' instrument = GetInstrFromXML(wbBook.FullName) With rs .AddNew ' create a new record ' add values to each field in the record .Fields("datapath") = dpath .Fields("analysistime") = atime .Fields("reporttime") = rtime .Fields("lastcalib") = lcalib .Fields("analystname") = aname .Fields("reportname") = rname .Fields("batchstate") = "bstate" .Fields("instrument") = "NA" .Update ' stores the new record End With what is the next step? how do i do an rs.execute?

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  • MySQL break out group clause from subquery

    - by Anton Gildebrand
    Here is my query SELECT COALESCE(js.name,'Lead saknas'), count(j.id) FROM jobs j LEFT JOIN job_sources js ON j.job_source=js.id LEFT JOIN (SELECT * FROM quotes GROUP BY job_id) q ON j.id=q.job_id GROUP BY j.job_source The problem is that it's allowed for each job to have more than one quote. Because of that i group the quotes by job_id. Now sure, this works. But i don't like the solution with a subquery. How can i break out the group clause from the subquery to the main query? I have tried to add q.job_id to the main group clause, both before and after the existing one but don't get the same results.

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  • Check if row already exists, if so tell the referenced table the id

    - by flhe
    Let's assume I have a table magazine: CREATE TABLE magazine ( magazine_id integer NOT NULL DEFAULT nextval(('public.magazine_magazine_id_seq'::text)::regclass), longname character varying(1000), shortname character varying(200), issn character varying(9), CONSTRAINT pk_magazine PRIMARY KEY (magazine_id) ); And another table issue: CREATE TABLE issue ( issue_id integer NOT NULL DEFAULT nextval(('public.issue_issue_id_seq'::text)::regclass), number integer, year integer, volume integer, fk_magazine_id integer, CONSTRAINT pk_issue PRIMARY KEY (issue_id), CONSTRAINT fk_magazine_id FOREIGN KEY (fk_magazine_id) REFERENCES magazine (magazine_id) MATCH SIMPLE ON UPDATE NO ACTION ON DELETE NO ACTION ); Current INSERTS: INSERT INTO magazine (longname,shotname,issn) VALUES ('a long name','ee','1111-2222'); INSERT INTO issue (fk_magazine_id,number,year,volume) VALUES (currval('magazine_magazine_id_seq'),'8','1982','6'); Now a row should only be inserted into 'magazine', if it does not already exist. However if it exists, the table 'issue' needs to get the 'magazine_id' of the row that already exists in order to establish the reference. How can i do this? Thx in advance!

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  • How to find all records that share the same field value as some other record?

    - by Gj
    I need to extract all records which have a field which does NOT have a unique value. I can't figure out an elegant way to do it - using annotation or some other way. I see a "value_annotate" method to the object manager but it's unclear if it's at all related. Currently I'm using the inelegant way of simple looping through all values and doing a get on the value, and if there's an exception it means it's not unique.. Thanks

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  • slow record deletion with large ntext values

    - by asking
    I'm having trouble deleting some records via a stored procedure from a table in SQLServer 2008R2 that has ntext columns. The stored proc is timing out and running the query directly takes a very long time. The initial query was a straight "delete from y where x = z" and I've also tried running it in batches of 1000 with transactions but it is still slow and timing out in a stored proc. The majority of the records in the table will not be deleted each time (it's not just a once-off query but will be run other times). The ntext columns are not used in the where clause and I can't change the column types. Any suggestions on the quickest way to delete records with large ntext values? Thanks

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  • (mySQL) Unable to query 2 tables properly for data

    - by Devner
    I have 2 tables. One is 'page_links' and the other is 'rpp'. Table page_links is the superset of table rpp. The following is the schema of my tables: -- Table structure for table `page_links` -- CREATE TABLE IF NOT EXISTS `page_links` ( `page` varchar(255) NOT NULL, `page_link` varchar(100) NOT NULL, `heading_id` tinyint(3) unsigned NOT NULL, PRIMARY KEY (`page`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; -- -- Dumping data for table `page_links` -- INSERT INTO `page_links` (`page`, `page_link`, `heading_id`) VALUES ('a1.php', 'A1', 8), ('b1.php', 'B1', 8), ('c1.php', 'C1', 5), ('d1.php', 'D1', 5), ('e1.php', 'E1', 8), ('f1.php', 'F1', 8), ('g1.php', 'G1', 8), ('h1.php', 'H1', 1), ('i1.php', 'I1', 1), ('j1.php', 'J1', 8), ('k1.php', 'K1', 8), ('l1.php', 'L1', 8), ('m1.php', 'M1', 8), ('n1.php', 'N1', 8), ('o1.php', 'O1', 8), ('p1.php', 'P1', 4), ('q1.php', 'Q1', 5), ('r1.php', 'R1', 4); -- Table structure for table `rpp` -- CREATE TABLE IF NOT EXISTS `rpp` ( `role_id` tinyint(3) unsigned NOT NULL, `page` varchar(255) NOT NULL, `is_allowed` tinyint(1) NOT NULL, PRIMARY KEY (`role_id`,`page`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; -- -- Dumping data for table `rpp` -- INSERT INTO `rpp` (`role_id`, `page`, `is_allowed`) VALUES (3, 'a1.php', 1), (3, 'b1.php', 1), (3, 'c1.php', 1), (3, 'd1.php', 1), (3, 'e1.php', 1), (3, 'f1.php', 1), (3, 'h1.php', 1), (3, 'i1.php', 1), (3, 'l1.php', 1), (3, 'm1.php', 1), (3, 'n1.php', 1), (4, 'a1.php', 1), (4, 'b1.php', 1), (4, 'q1.php', 1), (5, 'r1.php', 1); WHAT I AM TRYING TO DO: I am trying to query both the above tables (in a single query) in such a way that all the pages from page_links are displayed along with the is_allowed value from rpp for a particular role. For example, I want to get the is_allowed value of all the pages from rpp for role_id = 3 and at the same time, list all the available pages from page_links. A clear example of my expected result would be: page is_allowed role_id ---------------------------------------- a1.php 1 3 b1.php 1 3 c1.php 1 3 d1.php 1 3 e1.php 1 3 f1.php 1 3 g1.php NULL NULL h1.php 1 3 i1.php 1 3 j1.php NULL NULL k1.php NULL NULL l1.php 1 3 m1.php 1 3 n1.php 1 3 o1.php NULL NULL p1.php NULL NULL q1.php NULL NULL r1.php NULL NULL One more example of my desired result could be achieved by doing a LEFT JOIN rpp ON page_links.page = rpp.page but we need to omit using role_id = 3 (or any value) to be able to get that. But I do want to specify the role_id as well and get the results. I need the query to be able to get this result. I would appreciate any replies that could help me with this. If you can suggest me any changes as well to the table(s) design to be able to achieve the desired result, that's good as well. Thanks in advance.

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  • how to use two count or more on one selecting statament ..?

    - by jjj
    i develop this code: SELECT COUNT(NewEmployee.EmployeeID), NewEmployee.EmployeeId,EmployeeName FROM NewEmployee INNER JOIN NewTimeAttendance ON NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3) GROUP BY NewEmployee.EmployeeID, EmployeeName order by EmployeeID from my previous two question selecting null stuff and counting issue...that amazing code is working beautifully fine..but now i need to select more than one count... ...searched (google) .... found alias...tried: SELECT COUNT(NewEmployee.EmployeeID) as attenddays, COUNT(NewEmployee.EmployeeID) as empabsent , NewEmployee.EmployeeId,EmployeeName FROM NewEmployee INNER JOIN NewTimeAttendance ON empabsent =NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3) , attenddays = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3) GROUP BY NewEmployee.EmployeeID, EmployeeName order by EmployeeID Incorrect syntax near '='. second try: SELECT COUNT(NewEmployee.EmployeeID) as attenddays, COUNT(NewEmployee.EmployeeID) as absentdays, NewEmployee.EmployeeId,EmployeeName FROM NewEmployee INNER JOIN NewTimeAttendance ON attenddays(NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3)) , absentdays(NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3)) GROUP BY NewEmployee.EmployeeID, EmployeeName order by EmployeeID Incorrect syntax near '='. not very good ideas... so ...help thanks in advance

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  • How do I create a table in SQLite using the VS2008 Server Explorer

    - by fishhead
    Hello, I would like to create a table in a SQLite database using the Server Explorer in VS2008. I am able to do other operations on the database but when it comes to creating a table using the query builder I get Not Supported messages. is there another way other than writing code just for the sole purpose of creating the table? CREATE TABLE myTable ( ID INTEGER PRIMARY KEY AUTOINCREMENT, Name VARCHAR(100) ) .NET Framework Data Provider for SQLite 3.6.16

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  • ASP.Net delete record audit trigger

    - by Germ
    Suppose you have the following... A ASP.NET web application that calls a stored procedure to delete a record. The table has a trigger on it that will insert an audit entry each time a record is deleted. I want to be able to record in the audit entry the person who deleted the record. What would be the best way to go about achieving this? I know I could remove the trigger and have the delete stored procedure insert the audit entry prior to deleting but are there other recommeded alternative?

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  • How to map combinations of things to a relational database?

    - by Space_C0wb0y
    I have a table whose records represent certain objects. For the sake of simplicity I am going to assume that the table only has one row, and that is the unique ObjectId. Now I need a way to store combinations of objects from that table. The combinations have to be unique, but can be of arbitrary length. For example, if I have the ObjectIds 1,2,3,4 I want to store the following combinations: {1,2}, {1,3,4}, {2,4}, {1,2,3,4} The ordering is not necessary. My current implementation is to have a table Combinations that maps ObjectIds to CombinationIds. So every combination receives a unique Id: ObjectId | CombinationId ------------------------ 1 | 1 2 | 1 1 | 2 3 | 2 4 | 2 This is the mapping for the first two combinations of the example above. The problem is, that the query for finding the CombinationId of a specific Combination seems to be very complex. The two main usage scenarios for this table will be to iterate over all combinations, and the retrieve a specific combination. The table will be created once and never be updated. I am using SQLite through JDBC. Is there any simpler way or a best practice to implement such a mapping?

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  • Best way to get a reasonably random key for MYSQL records

    - by Steve N
    Hi there, I need to generate a reasonably random unique key for a table. It should be something like a GUID for MYSQL. I've tried UUID, but it looks like only the first few characters are actually random- the rest are the same every time I insert them. Essentially, it is desirable for this key field to be very difficult to guess, even if you already have one known value in the column. What is the best way to do this, and how should I set up the field data type to store the value efficiently? Thank you, Steve

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  • Linq Distinct() by name for populate a dropdown list with name and value

    - by AndreMiranda
    I'm trying to populate a Drop down list with pharmaceutical companies, like Bayer, Medley etc. And, I'm getting theses names from DB and theses names are repeated in DB, but with different id's. I'm trying to use Linq Distinct(), but I don't want to use the equality comparer. Is there another way? My drop down list must be filled with the id and the name of the company. I'm trying something like: var x = _partnerService .SelectPartners() .Select(c => new {codPartner = c.codPartner, name = c.name}) .Distinct(); This is showing repeated companies in ddl. thanks!

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