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  • Removing certain characters in all rows that match a regex?

    - by user001
    I'd like to change {foo, {bar}, foobar} to {foo, bar, foobar} in all rows that match '{.*{'. I.e. remove all curly braces { and } except the outer most pair. So doing mysql -h $H -u $U -p$P $DB -B -e "SELECT id FROM t WHERE col REGEXP '{.*{'" > bad.txt selects all the rows that will need this substitution. How do I make this substitution very quickly? EDIT: Could I do it by update table set column = REPLACE(column,'{',''); Then restore the out most pair update table set column = REPLACE(column,'^','{'); update table set column = REPLACE(column,'$','}');

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  • Why is this postgresql query so slow?

    - by user315975
    I'm no database expert, but I have enough knowledge to get myself into trouble, as is the case here. This query SELECT DISTINCT p.* FROM points p, areas a, contacts c WHERE ( p.latitude > 43.6511659465 AND p.latitude < 43.6711659465 AND p.longitude > -79.4677941889 AND p.longitude < -79.4477941889) AND p.resource_type = 'Contact' AND c.user_id = 6 is extremely slow. The points table has fewer than 2000 records, but it takes about 8 seconds to execute. There are indexes on the latitude and longitude columns. Removing the clause concering the resource_type and user_id make no difference. The latitude and longitude fields are both formatted as number(15,10) -- I need the precision for some calculations. There are many, many other queries in this project where points are compared, but no execution time problems. What's going on?

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  • MySQL, return only rows where there are duplicates among two columns.

    - by Richard Waite
    I have a table in MySQL of contact information ; first name, last name, address, etc. I would like to run a query on this table that will return only rows with first and last name combinations which appear in the table more than once. I do not want to group the "duplicates" (which may only be duplicates of the first and last name, but not other information like address or birthdate) - I want to return all the "duplicate" rows so I can look over the results and determine if they are dupes or not. This seemed like it would be a simple thing to do, but it has not been. Every solution I can find either groups the dupes and gives me a count only (which is not useful for what I need to do with the results) or doesn't work at all. Is this kind of logic even possible in a query ? Should I try and do this in Python or something?

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  • Ways to implement tags - pros and cons of each

    - by bobobobo
    Related Using SO as an example, what is the most sensible way to manage tags if you anticipate they will change often? Way 1: Seriously denormalized (comma delimited) table posts +--------+-----------------+ | postId | tags | +--------+-----------------+ | 1 | c++,search,code | Here tags are comma delimited. Pros: Tags are retrieved at once with a single select query. Updating tags is simple. Easy and cheap to update. Cons: Extra parsing on tag retrieval, difficult to count how many posts use which tags. (alternatively, if limited to something like 5 tags) table posts +--------+-------+-------+-------+-------+-------+ | postId | tag_1 | tag_2 | tag_3 | tag_4 | tag_5 | +--------+-------+-------+-------+-------+-------+ | 1 | c++ |search | code | | | Way 2: "Slightly normalized" (separate table, no intersection) table posts +--------+-------------------+ | postId | title | +--------+-------------------+ | 1 | How do u tag? | table taggings +--------+---------+ | postId | tagName | +--------+---------+ | 1 | C++ | | 1 | search | Pros: Easy to see tag counts (count(*) from taggings where tagName='C++'). Cons: tagName will likely be repeated many, many times. Way 3: The cool kid's (normalized with intersection table) table posts +--------+---------------------------------------+ | postId | title | +--------+---------------------------------------+ | 1 | Why is a raven like a writing desk? | table tags +--------+---------+ | tagId | tagName | +--------+---------+ | 1 | C++ | | 2 | search | | 3 | foofle | table taggings +--------+---------+ | postId | tagId | +--------+---------+ | 1 | 1 | | 1 | 2 | | 1 | 3 | Pros: No repeating tag names. More girls will like you. Cons: More expensive to change tags than way #1.

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  • MSSQL - Select one random record not showing duplicates

    - by Lukes123
    I have two tables, events and photos, which relate together via the 'Event_ID' column. I wish to select ONE random photo from each event and display them. How can I do this? I have the following which displays all the photos which are associated. How can I limit it to one per event? SELECT Photos.Photo_Id, Photos.Photo_Path, Photos.Event_Id, Events.Event_Title, Events.Event_StartDate, Events.Event_EndDate FROM Photos, Events WHERE Photos.Event_Id = Events.Event_Id AND Events.Event_EndDate < GETDATE() AND Events.Event_EndDate IS NOT NULL AND Events.Event_StartDate IS NOT NULL ORDER BY NEWID() Thanks Luke Stratton

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  • Stored procedure optimization

    - by George Zacharia
    Hi, i have a stored procedure which takes lot of time to execure .Can any one suggest a better approch so that the same result set is achived. ALTER PROCEDURE [dbo].[spFavoriteRecipesGET] @USERID INT, @PAGENUMBER INT, @PAGESIZE INT, @SORTDIRECTION VARCHAR(4), @SORTORDER VARCHAR(4),@FILTERBY INT AS BEGIN DECLARE @ROW_START INT DECLARE @ROW_END INT SET @ROW_START = (@PageNumber-1)* @PageSize+1 SET @ROW_END = @PageNumber*@PageSize DECLARE @RecipeCount INT DECLARE @RESULT_SET_TABLE TABLE ( Id INT NOT NULL IDENTITY(1,1), FavoriteRecipeId INT, RecipeId INT, DateAdded DATETIME, Title NVARCHAR(255), UrlFriendlyTitle NVARCHAR(250), [Description] NVARCHAR(MAX), AverageRatingId FLOAT, SubmittedById INT, SubmittedBy VARCHAR(250), RecipeStateId INT, RecipeRatingId INT, ReviewCount INT, TweaksCount INT, PhotoCount INT, ImageName NVARCHAR(50) ) INSERT INTO @RESULT_SET_TABLE SELECT FavoriteRecipes.FavoriteRecipeId, Recipes.RecipeId, FavoriteRecipes.DateAdded, Recipes.Title, Recipes.UrlFriendlyTitle, Recipes.[Description], Recipes.AverageRatingId, Recipes.SubmittedById, COALESCE(users.DisplayName,users.UserName,Recipes.SubmittedBy) As SubmittedBy, Recipes.RecipeStateId, RecipeReviews.RecipeRatingId, COUNT(RecipeReviews.Review), COUNT(RecipeTweaks.Tweak), COUNT(Photos.PhotoId), dbo.udfGetRecipePhoto(Recipes.RecipeId) AS ImageName FROM FavoriteRecipes INNER JOIN Recipes ON FavoriteRecipes.RecipeId=Recipes.RecipeId AND Recipes.RecipeStateId <> 3 LEFT OUTER JOIN RecipeReviews ON RecipeReviews.RecipeId=Recipes.RecipeId AND RecipeReviews.ReviewedById=@UserId AND RecipeReviews.RecipeRatingId= ( SELECT MAX(RecipeReviews.RecipeRatingId) FROM RecipeReviews WHERE RecipeReviews.ReviewedById=@UserId AND RecipeReviews.RecipeId=FavoriteRecipes.RecipeId ) OR RecipeReviews.RecipeRatingId IS NULL LEFT OUTER JOIN RecipeTweaks ON RecipeTweaks.RecipeId = Recipes.RecipeId AND RecipeTweaks.TweakedById= @UserId LEFT OUTER JOIN Photos ON Photos.RecipeId = Recipes.RecipeId AND Photos.UploadedById = @UserId AND Photos.RecipeId = FavoriteRecipes.RecipeId AND Photos.PhotoTypeId = 1 LEFT OUTER JOIN users ON Recipes.SubmittedById = users.UserId WHERE FavoriteRecipes.UserId=@UserId GROUP BY FavoriteRecipes.FavoriteRecipeId, Recipes.RecipeId, FavoriteRecipes.DateAdded, Recipes.Title, Recipes.UrlFriendlyTitle, Recipes.[Description], Recipes.AverageRatingId, Recipes.SubmittedById, Recipes.SubmittedBy, Recipes.RecipeStateId, RecipeReviews.RecipeRatingId, users.DisplayName, users.UserName, Recipes.SubmittedBy; WITH SortResults AS ( SELECT ROW_NUMBER() OVER ( ORDER BY CASE WHEN @SORTDIRECTION = 't' AND @SORTORDER='a' THEN TITLE END ASC, CASE WHEN @SORTDIRECTION = 't' AND @SORTORDER='d' THEN TITLE END DESC, CASE WHEN @SORTDIRECTION = 'r' AND @SORTORDER='a' THEN AverageRatingId END ASC, CASE WHEN @SORTDIRECTION = 'r' AND @SORTORDER='d' THEN AverageRatingId END DESC, CASE WHEN @SORTDIRECTION = 'mr' AND @SORTORDER='a' THEN RecipeRatingId END ASC, CASE WHEN @SORTDIRECTION = 'mr' AND @SORTORDER='d' THEN RecipeRatingId END DESC, CASE WHEN @SORTDIRECTION = 'd' AND @SORTORDER='a' THEN DateAdded END ASC, CASE WHEN @SORTDIRECTION = 'd' AND @SORTORDER='d' THEN DateAdded END DESC ) RowNumber, FavoriteRecipeId, RecipeId, DateAdded, Title, UrlFriendlyTitle, [Description], AverageRatingId, SubmittedById, SubmittedBy, RecipeStateId, RecipeRatingId, ReviewCount, TweaksCount, PhotoCount, ImageName FROM @RESULT_SET_TABLE WHERE ((@FILTERBY = 1 AND SubmittedById= @USERID) OR ( @FILTERBY = 2 AND (SubmittedById <> @USERID OR SubmittedById IS NULL)) OR ( @FILTERBY <> 1 AND @FILTERBY <> 2)) ) SELECT RowNumber, FavoriteRecipeId, RecipeId, DateAdded, Title, UrlFriendlyTitle, [Description], AverageRatingId, SubmittedById, SubmittedBy, RecipeStateId, RecipeRatingId, ReviewCount, TweaksCount, PhotoCount, ImageName FROM SortResults WHERE RowNumber BETWEEN @ROW_START AND @ROW_END print @ROW_START print @ROW_END SELECT @RecipeCount=dbo.udfGetFavRecipesCount(@UserId) SELECT @RecipeCount AS RecipeCount SELECT COUNT(Id) as FilterCount FROM @RESULT_SET_TABLE WHERE ((@FILTERBY = 1 AND SubmittedById= @USERID) OR (@FILTERBY = 2 AND (SubmittedById <> @USERID OR SubmittedById IS NULL)) OR (@FILTERBY <> 1 AND @FILTERBY <> 2)) END

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  • PostgreSQL: How to index all foreign keys?

    - by biggusjimmus
    I am working with a large PostgreSQL database, and I are trying to tune it to get more performance. Our queries and updates seem to be doing a lot of lookups using foreign keys. What I would like is a relatively simple way to add Indexes to all of our foreign keys without having to go through every table (~140) and doing it manually. In researching this, I've come to find that there is no way to have Postgres do this for you automatically (like MySQL does), but I would be happy to hear otherwise there, too.

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  • Parse both symbols . and , as decimal digits delimiter in ASP.NET

    - by abatishchev
    I'm writing a banking system and my customer wants support both Russian and American numeric standards in decimal digits delimiter. Respectively . and ,. Now only , works properly. Perhaps because of web server's OS format (Russian is set). String like 2000.00 throws a FormatException: Input string was not in a correct format. How to fix that? Are there any other ideas except String.Replace('.', ',') on FormView.ItemInserting event?

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  • Best method to search hierarchical data

    - by WDuffy
    I'm looking at building a facility which allows querying for data with hierarchical filtering. I have a few ideas how I'm going to go about it but was wondering if there are any recommendations or suggestions that might be more efficient. As an example imagine that a user is searching for a job. The job areas would be as follows. 1: Scotland 2: --- West Central 3: ------ Glasgow 4: ------ Etc 5: --- North East 6: ------ Ayrshire 7: ------ Etc A user can search specific (i.e. Glasgow) or in a larger area (i.e. Scotland). The two approaches I am considering are: keep a note of children in the database for each record (i.e. cat 1 would have 2, 3, 4 in its children field) and query against that record with a SELECT * FROM Jobs WHERE Category IN Areas.childrenField. Use a recursive function to find all results who have a relation to the selected area. The problems I see from both are: Holding this data in the db will mean having to keep track of all changes to structure. Recursion is slow and inefficent. Any ideas, suggestion or recommendations on the best approach? I'm using C# ASP.NET with MSSQL 2005 DB.

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  • form not showing for empty records

    - by Chris Hodges
    I have a relatively simple PHP page called editcustomers with 3 columns. The problem I'm having is that the form will show when there is a record in the database and the fields will be populated with that info. When no such records exists, the form is not even shown, eliminating the possibility to insert a record. My page layout is as follows: Column 1 shows a form containing customer information, allowing it to be edited. Column 2 allows ordering of products and showing how many products were ordered Column 3 shows the total paid so far, and the total owing. The code for the page I have at present: <html> <?php $id = $_GET['id']; require_once('connect.php'); $sth = $dbh->query("SELECT * FROM users where id = '$id';"); $sth->setFetchMode(PDO::FETCH_ASSOC); $eth = $dbh->query("SELECT * FROM purchases where id = '$id';"); $eth->setFetchMode(PDO::FETCH_ASSOC); ?> <div id="main"> <div id="left"> <form name="custInfo" action ="process.php" method ="post" > <input type = "hidden" name ="formType" value="custInfo"/> <?php while($row = $sth->fetch()){ ?> <p><input type = "hidden" name ="id" value="<?php echo $row["id"] ?>"/> <p><input type = "text" name ="firstName" size ="30" value=" <?php echo $row["firstName"]?>"/> <p><input type = "text" name ="lastName" size ="30" value="<?php echo $row["lastName"]?>"/> <p><input type = "text" name ="country" size ="30" value="<?php echo $row["country"]?>"/> <p></p> <input type="submit" value="Update" /> <?php }?> </div> <div id="mid"> <form name="custCosts" action ="process.php" method ="post" > <input type = "hidden" name ="formType" value="custCosts"/> <?php while($row = $eth->fetch()){ ?> <p><input type = "hidden" name ="id" value="<?php echo $row["id"] ?>"/> <p><input type = "text" name ="amountOwed" size ="30" value=" <?php echo $row["amountOwed"]?>"/> <p><input type = "text" name ="numAaa" size ="30" value="<?php echo $row["numAaa"]?>"/> <p><input type = "text" name ="numBbb" size ="30" value="<?php echo $row["numBbb"]?>"/> <p></p> <input type="submit" value="Update" /> <?php }?> </div> <div id="right"> <b>Total Balance</b> <p> Money owed: </p> <p> aaa total: </p> <p> bbb total: </p> <p> Total: </p> <input type = "text" name ="pay" size ="20" /></p> <input type="submit" value="Make Payment" /> </div> <?php $dbh =null; ?> </body> </html> And the code for all the database trickery: <?php require_once 'connect.php'; $formType = $_POST['formType']; $id = $_POST['id']; $firstName = $_POST['firstName']; $lastName = $_POST['lastName']; $country = $_POST['country']; $amountOwed = $_POST['amountOwed ']; $numAaa = $_POST['numAaa']; $numBbb = $_POST['numBbb']; if(empty($_POST['id'])) { $sth = $dbh->prepare("INSERT INTO customers (firstName, lastName, country) VALUES ('$firstName', '$lastName', '$country')"); $sth->execute(); } elseif(!empty($_POST['id']) && !isset($_POST['stayCost']) && $_POST['formType'] == 'guestInfo'){ $sth = $dbh->prepare("UPDATE customers SET firstName = '$firstName', lastName = '$lastName', country = '$country' WHERE id = '$id'"); $sth->execute(); }elseif(!empty($_POST['id']) && isset($_POST['stayCost']) && $_POST['formType'] == 'guestInfo'){ $sth = $dbh->prepare("INSERT INTO purchases (id, amountOwed, numAaa, numBbb) VALUES ('$id', '$amountOwed', '$numAaa', '$numBbb'"); $sth->execute(); }elseif(!empty($_POST['id']) && $_POST['formType'] == 'guestCosts'){ $sth = $dbh->prepare("UPDATE purchases SET amountOwed= '$amountOwed', numAaa = '$numAaa', numBbb= '$numBbb' WHERE id = '$id'"); $sth->execute(); } $dbh =null; ?> Why does the form not even display if there is no record? An error or something I might understand....but the form is still in the HTML and should still be being output, from what I can see. Why is this not the case?

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  • MYSQL: How to limit inner join?

    - by Sergii Rechmp
    I need some help with my query. I have 2 tables: all: art|serie sootv: name|art|foo I need to get result like name|serie. My query is: SELECT t2.NAME, t1.serie FROM ( SELECT * FROM `all` WHERE `serie` LIKE '$serie' ) t1 INNER JOIN sootv t2 ON t1.art = t2.art; it works, but sootv table contains data like name|art|foo abc | 1 | 5 abc | 1 | 6 i get 2 same results. Its not what i need. Help me please - how i can get only one result: abc|1 Thanks.

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  • Insert not working

    - by user1642318
    I've searched evreywhere and tried all suggestions but still no luck when running the following code. Note that some code is commented out. Thats just me trying different things. SqlConnection connection = new SqlConnection("Data Source=URB900-PC\SQLEXPRESS;Initial Catalog=usersSQL;Integrated Security=True"); string password = PasswordTextBox.Text; string email = EmailTextBox.Text; string firstname = FirstNameTextBox.Text; string lastname = SurnameTextBox.Text; //command.Parameters.AddWithValue("@UserName", username); //command.Parameters.AddWithValue("@Password", password); //command.Parameters.AddWithValue("@Email", email); //command.Parameters.AddWithValue("@FirstName", firstname); //command.Parameters.AddWithValue("@LastName", lastname); command.Parameters.Add("@UserName", SqlDbType.VarChar); command.Parameters["@UserName"].Value = username; command.Parameters.Add("@Password", SqlDbType.VarChar); command.Parameters["@Password"].Value = password; command.Parameters.Add("@Email", SqlDbType.VarChar); command.Parameters["@Email"].Value = email; command.Parameters.Add("@FirstName", SqlDbType.VarChar); command.Parameters["@FirstName"].Value = firstname; command.Parameters.Add("@LasttName", SqlDbType.VarChar); command.Parameters["@LasttName"].Value = lastname; SqlCommand command2 = new SqlCommand("INSERT INTO users (UserName, Password, UserEmail, FirstName, LastName)" + "values (@UserName, @Password, @Email, @FirstName, @LastName)", connection); connection.Open(); command2.ExecuteNonQuery(); //command2.ExecuteScalar(); connection.Close(); When I run this, fill in the textboxes and hit the button I get...... Must declare the scalar variable "@UserName". Any help would be greatly appreciated. Thanks.

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  • sql data source

    - by George
    I have a table (EmployeeID,EmployeeName,ManagerID) How can I create a sqldatasource to include the ManagerName from the EmployeeName given EmployeeID = ManagerID? In my gridview after dragging a dropdownlist what bindings should I do to display the managerName? Is it possible to use it without writing custom select,insert,delete,update? If not what are the steps I need to do to write the whole thing i.e. custom grid and source? Thank you very much

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  • JOIN (SELECT DISTINCT [..] substitute

    - by FRKT
    Hello, I'd like to find a substitute for using SELECT DISTINCT in a derived table. Let's say I have three tables: CREATE TABLE `trades` ( `tradeID` int(11) unsigned NOT NULL AUTO_INCREMENT, `employeeID` int(11) unsigned NOT NULL, `corporationID` int(11) unsigned NOT NULL, `profit` int(11) NOT NULL, KEY `tradeID` (`tradeID`), KEY `employeeID` (`employeeID`), KEY `corporationID` (`corporationID`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 CREATE TABLE `corporations` ( `corporationID` int(11) unsigned NOT NULL AUTO_INCREMENT, `name` varchar(255) NOT NULL, PRIMARY KEY (`corporationID`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 CREATE TABLE `employees` ( `employeeID` int(11) unsigned NOT NULL AUTO_INCREMENT, `name` varchar(255) NOT NULL, PRIMARY KEY (`employeeID`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 Let's say I'd like to find out how much profit a specific employee has generated. Simple: SELECT SUM(profit) FROM trades JOIN employees ON trades.employeeID = employees.employeeID AND employees.employeeID = 1; It gets trickier if I'd like to query how much revenue a specific corporation has, however. I cannot simply replicate the aforementioned query, because two or more employees from the same company might be involved in the same trade. This query should do the trick: SELECT SUM(profit) FROM trades JOIN (SELECT DISTINCT tradeID FROM trades WHERE trades.corporationID = 1) ... unfortunately, DISTINCT JOINs seem crazy ineffective. Is there any alternative I can use to determine how much revenue a corporation has, taking into account that a corporation might be listed several times with the same tradeID?

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  • join select from multiple row values?

    - by user1869132
    Two tables 1) product -------------------- id | Name | price 1 | p1 | 10 2 | p2 | 20 3 | p3 | 30 2) product_attributes: --------------------------------------------------- id | product_id | attribute_name | attribute_value --------------------------------------------------- 1 | 1 | size | 10 2 | 1 | colour | red 3 | 2 | size | 20 I need to join these two tables. In the where clause I need to match both the two rows attribute values. Is it possible to get the result based on two rows value. Here if size=10 and colour=red. Output should be 1 | p1 | 10 It could be greatly helpful to get a query for this.

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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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  • Circular database relationships. Good, Bad, Exceptions?

    - by jim
    I have been putting off developing this part of my app for sometime purely because I want to do this in a circular way but get the feeling its a bad idea from what I remember my lecturers telling me back in school. I have a design for an order system, ignoring the everything that doesn't pertain to this example I'm left with: CreditCard Customer Order I want it so that, Customers can have credit cards (0-n) Customers have orders (1-n) Orders have one customer(1-1) Orders have one credit card(1-1) Credit cards can have one customer(1-1) (unique ids so we can ignore uniqueness of cc number, husband/wife may share cc instances ect) Basically the last part is where the issue shows up, sometimes credit cards are declined and they wish to use a different one, this needs to update which their 'current' card is but this can only change the current card used for that order, not the other orders the customer may have on disk. Effectively this creates a circular design between the three tables. Possible solutions: Either Create the circular design, give references: cc ref to order, customer ref to cc customer ref to order or customer ref to cc customer ref to order create new table that references all three table ids and put unique on the order so that only one cc may be current to that order at any time Essentially both model the same design but translate differently, I am liking the latter option best at this point in time because it seems less circular and more central. (If that even makes sense) My questions are, What if any are the pros and cons of each? What is the pitfalls of circular relationships/dependancies? Is this a valid exception to the rule? Is there any reason I should pick the former over the latter? Thanks and let me know if there is anything you need clarified/explained. --Update/Edit-- I have noticed an error in the requirements I stated. Basically dropped the ball when trying to simplify things for SO. There is another table there for Payments which adds another layer. The catch, Orders can have multiple payments, with the possibility of using different credit cards. (if you really want to know even other forms of payment). Stating this here because I think the underlying issue is still the same and this only really adds another layer of complexity.

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  • Oracle sql developer can acess from loalhost but not ip address

    - by Welcome Always
    Here i have installed widows server 2008 64 orale 11g r2 64 now i want to access this from the ip address that i have set to my server not working i can't access trough the ip address.... when i use on my application .....local host it can get connected but when i add the ip for example 10.0.0.2 it's not connecting now simply also on local when i write the ip address it's not connecting but with localhost works fine..... so even i have used listener. regards

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  • Queue access to the database to avoid multiple cache items

    - by MikeJ
    I have a music related ASP.NET web site which caches a lot of static information from the database on the first request. Sometimes, the application is reset and cache is cleared while the application is on heavy load and then all http requests go to the database to retrieve that static data and cache it for other requests. How can I ensure that only one request go to the database and cache the results, so that other request simply read that info from cache and not needlessly retrieve the same info over and over again. Can I use thread locking? For example, can I do something like lock(this) { db access here }?

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  • Dynamic where clause in LINQ - with column names available at runtime

    - by sandesh247
    Disclaimer: I've solved the problem using Expressions from System.Linq.Expressions, but I'm still looking for a better/easier way. Consider the following situation : var query = from c in db.Customers where (c.ContactFirstName.Contains("BlackListed") || c.ContactLastName.Contains("BlackListed") || c.Address.Contains("BlackListed")) select c; The columns/attributes that need to be checked against the blacklisted term are only available to me at runtime. How do I generate this dynamic where clause? An additional complication is that the Queryable collection (db.Customers above) is typed to a Queryable of the base class of 'Customer' (say 'Person'), and therefore writing c.Address as above is not an option.

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  • Databinding expression for retrieving value of related collection using LINQ

    - by joshb
    I have a GridView that is bound to a LINQDataSource control that is returning a collection of customers. Within my DataGrid I need to display the home phone number of a customer, if they have one. The phone numbers of a customer are stored in a separate table with a foreign key pointing to the customer table. The following binding expression gets me the first phone number for a customer: <asp:TemplateField HeaderText="LastName" SortExpression="LastName"> <ItemTemplate> <asp:Label ID="PhoneLabel" runat="server" Text='<%# Eval("Phones[0].PhoneNumber") %>'></asp:Label> </ItemTemplate> </asp:TemplateField> I need to figure out how to get the home phone number specifically (filter based on phone type) and handle the scenario where the customer does not have a home phone in the database. Right now it's throwing an out of range exception if the customer does not have any phone numbers. I've tried using the Where operator with a lambda expression to filter the phone type but it doesn't work: <%# Eval("Phones.Where(p => p.PhoneTypeId == 2).PhoneNumber") %> Solutions or links to any good articles on the subject would be much appreciated.

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