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  • How can I count existing and non-existing values with MySQL?

    - by jaya malladi
    I am new to MySQL. I have a table with answer ids. Answers can look like this:a1, a2, a3 ..., but due to some problems some are NULL, some are blank, and some are others like 1 a etc. Now I want to calculate the count of ids with a1 a2 a3 distinctly. But how is it possible to do this leaving others like NULL, blanks and garbage. The output should look like this atype count a1 45 a2 0 a3 56 If there is no row entry for a particular answer, the count should be 0.

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  • Can a primary key be equal to a different column?

    - by eric
    I know that a primary key must be unique, but is it okay for a primary key to be equal to a different column in the same table by coincidence? For instance, I have 2 tables. One table is called person that holds information about a person (ID, email, telephone, address, name). The other table is staff (ID, pID(person ID), salary, position). In staff the ID column is the primary key and is used to uniquely identify a staff member. The number is from 1 - 100. However, the pID (person ID) may be equal to the ID. For instance the staff ID may be 1 and the pID that it references to may be equal to 1. Is that okay?

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  • Selecting financial values from db stored as text

    - by Midhat
    I have some financial values stored as text in a mysql db. the significance of financial is that negative numbers are stored enclosed in paranthesis. is there a way to automatically get the numeric value associated with that text. (like '5' shoudl be retuned as 5 and '(5)' should be returned as -5)

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  • Session or Query

    - by Khou
    Should I store the user's ID, name & email address in a session variable or should I query for the user's user's ID, name & email address everytime i need to use it?

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  • c# Column datatype Date type (NOT DateTime)

    - by Sha Le
    Hi All: I want know is there good way to detect Column DataType for Date field (NOT DateTime)? This what currently I do: switch (dt.Columns[col].DataType.FullName) { case "System.DateTime": formatedVal = Formatter.GetDateTime(val); break; // which is NOT possible, but something equivalent am looking for case "System.Date": formatedVal = Formatter.GetDate(val); break; default: formatedVal = val.ToString(); break; } Thanks a bunch. :-)

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  • How can i pull an image and data from a Database?

    - by user1851377
    I am trying to pull data from a Database using C#.net and use a Foreach loop to make it visible on a page. Every time i run the code i only get one item that shows up when i know that there is at least 7 items in the DB. i have placed the code below for the C#. SqlConnection oConnection = new SqlConnection(ConfigurationManager.ConnectionStrings["HomeGrownEnergyConnectionString"].ToString()); string sqlEnergy = "Select * from Product p where p.ProductTypeId=3"; SqlCommand oCmd = new SqlCommand(sqlEnergy, oConnection); DataTable dtenergy = new DataTable(); SqlDataAdapter oDa = new SqlDataAdapter(oCmd); try { oConnection.Open(); ; oDa.Fill(dtenergy); } catch (Exception ex) { lblnodata.Text = ex.Message; return; } finally { oConnection.Close(); } DataTableReader results = dtenergy.CreateDataReader(); if (results.HasRows) { results.Read(); foreach(DataRow result in dtenergy.Rows) { byte[] imgProd = result["ThumnailLocation"] as byte[]; ID.Text = result["ProductID"].ToString(); Name.Text = result["Name"].ToString(); price.Text = FormatPriceColumn(result["Price"].ToString()); } } Here is the code for the asp.net. <div> <asp:Image ID="imgProd" CssClass="ProdImg" runat="server" /> <asp:Label runat="server" ID="ID" /> <asp:Label runat="server" ID="Name" /> <asp:Label runat="server" ID="price" /> <asp:TextBox ID="txtQty" MaxLength="3" runat="server" Width="30px" /> <asp:Button runat="server" ID="Addtocart" Text="Add To Cart" CommandName="AddToCart" ItemStyle-CssClass="btnCol" /> If someone could please help me that would be great thanks.

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  • asp:QueryStringParameter and empty query string parameter

    - by abatishchev
    I haveasp:GridView displaying client requests using asp:SqlDataSource. I want to limit displayed information by client: View.aspx has to display everything, View.aspx?client=1 has to display only requests from client ID #1. So I'm using <asp:QueryStringParameter Name="client" QueryStringField="client" /> for query "EXEC getRequests @client". Everything works properly when some client is specified. But don't - if not. I tested my SP using SSMS - it works properly in both cases - when parameter is specified and when it isn't (NULL passed explicitly). What have I do?

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  • Query to find duplicate item in 2 table

    - by Rico
    I have this table Antecedent Consequent I1 I2 I1 I1,I2,I3 I1 I4,I1,I3,I4 I1,I2 I1 I1,I2 I1,I4 I1,I2 I1,I3 I1,I4 I3,I2 I1,I2,I3 I1,I4 I1,I3,I4 I4 AS you can see it's pretty messed up. is there anyway i can remove rows if item in consequent exist in antecedent (in 1 row) for example: INPUT: Antecedent Consequent I1 I2 I1 I1,I2,I3 <---- DELETE since I1 exist in antecedent I1 I4,I1,I3,I4 <---- DELETE since I1 exist in antecedent I1,I2 I1 <---- DELETE since I1 exist in antecedent I1,I2 I1,I4 <---- DELETE since I1 exist in antecedent I1,I2 I1,I3 <---- DELETE since I1 exist in antecedent I1,I4 I3,I2 I1,I2,I3 I1,I4 <---- DELETE since I1 exist in antecedent I1,I3,I4 I4 <---- DELETE since I4 exist in antecedent OUTPUT: Antecedent Consequent I1 I2 I1,I4 I3,I2 is there anyway i can do that by query?

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  • 100+ tables to joined

    - by deian
    Hi guys, I was wondering if anyone ever had a change to measure how a would 100 joined tables perform? Each table would have an ID column with primary index and all table are 1:1 related. It is a common problem within many data entry applications where we need to collect 1000+ data points. One solution would be to have one big table with 1000+ columns and the alternative would be to split them into multiple tables and join them when it is necessary. So perhaps more real question would be how 30 tables (30 columns each) would behave with multitable join. 500K-1M rows should be the expected size of the tables. Cheers

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  • Copy new records from datatable and identify changes in old records

    - by Betite
    Assume there are two tables: Remote_table and My_table. Remote_table has 6 columns: **PROJECT JOB_TYPE MONTH YEAR** HOURS IS_DELETED 134393 70 1 2013 30 0 134393 70 2 2013 50 0 134393 70 3 2013 80 0 134393 70 10 2012 10 0 134393 70 11 2012 0 0 134393 70 12 2012 15 0 My_table is a copy of remote_table. I tried to copy only the new records from the remote_table by this query: SELECT * FROM [remote_DB].[LudanProjectManager].[dbo].Remote_table EXCEPT SELECT * FROM My_table It works OK but I get a duplicate primary key exception when changes have been made on the remote_table on the hours column. Can anyone think of a way to copy only the new records from remote_table and if changes has been made on old records, to identify them and update the my_table to correspond?

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  • Naming of boolean column in database table

    - by Space Cracker
    I have 'Service' table and the following column description as below Is User Verification Required for service ? Is User's Email Activation Required for the service ? Is User's Mobile Activation required for the service ? I Hesitate in naming these columns as below IsVerificationRequired IsEmailActivationRequired IsMobileActivationRequired or RequireVerification RequireEmailActivation RequireMobileActivation I can't determined which way is the best .So, Is one of the above suggested name is the best or is there other better ones ?

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  • CLR: Multi Param Aggregate, Argument not in Final Output?

    - by OMG Ponies
    Why is my delimiter not appearing in the final output? It's initialized to be a comma, but I only get ~5 white spaces between each attribute using: SELECT [article_id] , dbo.GROUP_CONCAT(0, t.tag_name, ',') AS col FROM [AdventureWorks].[dbo].[ARTICLE_TAG_XREF] atx JOIN [AdventureWorks].[dbo].[TAGS] t ON t.tag_id = atx.tag_id GROUP BY article_id The bit for DISTINCT works fine, but it operates within the Accumulate scope... Output: article_id | col ------------------------------------------------- 1 | a a b c I only have rudimentary C# API knowledge... C# Code: using System; using System.Data; using System.Data.SqlClient; using System.Data.SqlTypes; using Microsoft.SqlServer.Server; using System.Xml.Serialization; using System.Xml; using System.IO; using System.Collections; using System.Text; [Serializable] [SqlUserDefinedAggregate(Format.UserDefined, MaxByteSize = 8000)] public struct GROUP_CONCAT : IBinarySerialize { ArrayList list; string delimiter; public void Init() { list = new ArrayList(); delimiter = ","; } public void Accumulate(SqlBoolean isDistinct, SqlString Value, SqlString separator) { delimiter = (separator.IsNull) ? "," : separator.Value ; if (!Value.IsNull) { if (isDistinct) { if (!list.Contains(Value.Value)) { list.Add(Value.Value); } } else { list.Add(Value.Value); } } } public void Merge(GROUP_CONCAT Group) { list.AddRange(Group.list); } public SqlString Terminate() { string[] strings = new string[list.Count]; for (int i = 0; i < list.Count; i++) { strings[i] = list[i].ToString(); } return new SqlString(string.Join(delimiter, strings)); } #region IBinarySerialize Members public void Read(BinaryReader r) { int itemCount = r.ReadInt32(); list = new ArrayList(itemCount); for (int i = 0; i < itemCount; i++) { this.list.Add(r.ReadString()); } } public void Write(BinaryWriter w) { w.Write(list.Count); foreach (string s in list) { w.Write(s); } } #endregion }

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  • Rails 3 fields_for agressive loading?

    - by Seth
    Hi all, I'm trying to optimize (limit) queries in a view. I am using the fields_for function. I need to reference various properties of the object, such as username for display purposes. However, this is a rel table, so I need to join with my users table. The result is N sub-queries, 1 for each field in fields_for. It's difficult to explain, but I think you'll understand what I'm asking if I paste my code: <%= form_for @election do |f| %> <%= f.fields_for :voters do |voter| %> <%= voter.hidden_field :id %> <%= voter.object.user.preferred_name %> <% end %> <% end %> I have like 10,000 users, and many times each election will include all 10,000 users. That's 10,000 subqueries every time this view is loaded. I want fields_for to JOIN on users. Is this possible? I'd like to do something like: ... <%= f.fields_for :voters, :joins => :users do |voter| %> ... <% end %> ... But that, of course, doesn't work :(

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  • Can't delete record via the datacontext it was retrieved from

    - by Antilogic
    I just upgraded one of my application's methods to use compiled queries (not sure if this is relevant). Now I'm getting contradicting error messages when I run the code. This is my method: MyClass existing = Queries.MyStaticCompiledQuery(MyRequestScopedDataContext, param1, param2).SingleOrDefault(); if (existing != null) { MyRequestScopedDataContext.MyClasses.DeleteOnSubmit(existing); } When I run it I get this message: Cannot remove an entity that has not been attached. Note that the compiled query and the DeleteOnSubmit reference the same DataContext. Still I figured I'd humor the application and add an attach command before the DeleteOnSubmit, like so: MyClass existing = Queries.MyStaticCompiledQuery(MyRequestScopedDataContext, param1, param2).SingleOrDefault(); if (existing != null) { MyRequestScopedDataContext.MyClasses.Attach(existing); MyRequestScopedDataContext.MyClasses.DeleteOnSubmit(existing); } BUT... When I run this code, I get a completely different contradictory error message: An attempt has been made to Attach or Add an entity that is not new, perhaps having been loaded from another DataContext. This is not supported. I'm at a complete loss... Does anyone else have some insight as to why I can't delete a record via the same DataContext I retrieved it from?

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  • Connecting PHP Server and Android?

    - by user3439988
    I am trying to create a simple test application to transfer data back and forth between my server and Android device. The following are the things I aim for: Ability to upload data and files to the server. To be able to view my files on the server. To be able to download the files from the server to my android device. Ability of the server to send me updates on the files or notifications to my phone. I need a safe and secure way to do these things. I have tried these: HTTPPost requests onto the server and echoing the output accordingly and capturing the HTTPresponse and parsing it. For files I have tried using MultipartEntity, but I think that has been deprecated.

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  • How to SUM columns on multiple conditions in a GROUP BY

    - by David Liddle
    I am trying to return a list of Accounts with their Balances, Outcome and Income Account Transaction ------- ----------- AccountID TransactionID BankName AccountID Locale Amount Status Here is what I currently have. Could someone explain where I am going wrong? select a.ACCOUNT_ID, a.BANK_NAME, a.LOCALE, a.STATUS, sum(t1.AMOUNT) as BALANCE, sum(t2.AMOUNT) as OUTCOME, sum(t3.AMOUNT) as INCOME from ACCOUNT a left join TRANSACTION t1 on t1.ACCOUNT_ID = a.ACCOUNT_ID left join TRANSACTION t2 on t1.ACCOUNT_ID = a.ACCOUNT_ID and t2.AMOUNT < 0 left join TRANSACTION t3 on t3.ACCOUNT_ID = a.ACCOUNT_ID and t3.AMOUNT > 0 group by a.ACCOUNT_ID, a.BANK_NAME, a.LOCALE, a.[STATUS]

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  • connecting to mysql from excel: ODBC driver does not support the requested properties.

    - by every_answer_gets_a_point
    i am trying to add data to mysql from excel. i am getting the above error on this line: rs.Open strSQL, oConn, adOpenDynamic, adLockOptimistic here is my code: Dim oConn As ADODB.Connection Private Sub ConnectDB() Set oConn = New ADODB.Connection oConn.Open "DRIVER={MySQL ODBC 5.1 Driver};" & _ "SERVER=localhost;" & _ "DATABASE=employees;" & _ "USER=root;" & _ "PASSWORD=some_pass;" & _ "Option=3" End Sub Function esc(txt As String) esc = Trim(Replace(txt, "'", "\'")) End Function Private Sub InsertData() Dim rs As ADODB.Recordset Set rs = New ADODB.Recordset ConnectDB With wsBooks For rowCursor = 2 To 11 strSQL = "INSERT INTO tutorial (author, title, price) " & _ "VALUES ('" & esc(.Cells(rowCursor, 1)) & "', " & _ "'" & esc(.Cells(rowCursor, 2)) & "', " & _ esc(.Cells(rowCursor, 3)) & ")" rs.Open strSQL, oConn, adOpenDynamic, adLockOptimistic Next End With End Sub whats wrong with rs.Open strSQL, oConn, adOpenDynamic, adLockOptimistic ? why am i getting the odbc error?

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  • Return multiple IDs from a function and use the result in a query

    - by NewK
    I have this function that returns me all children of a tree node: CREATE OR REPLACE FUNCTION fn_category_get_childs_v2(id_pai integer) RETURNS integer[] AS $BODY$ DECLARE ids_filhos integer array; BEGIN SELECT array ( SELECT category_id FROM category WHERE category_id IN ( (WITH RECURSIVE parent AS ( SELECT category_id , parent_id from category WHERE category_id = id_pai UNION ALL SELECT t.category_id , t.parent_id FROM parent INNER JOIN category t ON parent.category_id = t.parent_id ) SELECT category_id FROM parent WHERE category_id <> id_pai ) ) ) into ids_filhos; return ids_filhos; END; and I would like to use it in a select statement like this: select * from teste1_elements where category_id in (select * from fn_category_get_childs_v2(12)) I've also tried this way with the same result: select * from teste1_elements where category_id=any(select * from fn_category_get_childs_v2(12))) But I get the following error: ERROR: operator does not exist: integer = integer[] LINE 1: select * from teste1_elements where category_id in (select *... ^ HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts. The function returns an integer array, is that the problem? SELECT * from fn_category_get_childs_v2(12) retrieves the following array (integer[]): '{30,32,34,20,19,18,17,16,15,14}'

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  • postgres subquery w/ derived column

    - by Wells
    The following query won't work, but it should be clear what I'm trying to do: split the value of 't' on space and use the last element in that array in the subquery (as it will match tl). Any ideas how to do this? Thanks! SELECT t, y, "type", regexp_split_to_array(t, ' ') as t_array, sum(dr), ( select uz from f.tfa where tl = t_array[-1] ) as uz, sc FROM padres.yd_fld WHERE y = 2010 AND pos <> 0 GROUP BY t, y, "type", sc;

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  • Maintaining stored procedures in source control

    - by dub
    How do you guys maintain your stored procedures? I'd like to keep versions of them for a few different reasons. I also will be setting up cruisecontrol.net and nant this weekend to automate builds. I was thinking about coding something that would generate the create scripts for all tables/sprocs/udf/xml schemas in my development database. Then it would take those scripts and update them in source control every couple hours.... Ideally, I'd like to make this some sort of plugin/module for cruisecontrol.net. Any other ideas?

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  • Evaluate column value into rows

    - by Hugo Palma
    I have a column whose value is a json array. For example: [{"att1": "1", "att2": "2"}, {"att1": "3", "att2": "4"}, {"att1": "5", "att2": "6"}] What i would like is to provide a view where each element of the json array is transformed into a row and the attributes of each json object into columns. Keep in mind that the json array doesn't have a fixed size. Any ideas on how i can achieve this ?

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