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  • mysql join 3 tables and count

    - by air
    Please look at this image here is 3 tables , and out i want is uid from table1 industry from table 3 of same uid count of fid from table 2 of same uid like in the sample example output will be 2 records Thanks

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  • How to update a record with multiple keys

    - by OceanBlue
    I am trying a database app on Android. I want to use the SQLiteDatabase update(...) convenience method to update a record. Normally, for a WHERE clause of a single key this is working. Following code is working fine:- values.put("testname", "Quiz1"); mDB.update("Tests", values, "id=?", new String[]{"2"}); //this statement works However, I want to update a column in a table which has a combination of two keys as the unique identifier. I tried the following. This executes without exception, but nothing is updated. values.put("score", 60); mDB.update("Results", values, "studentid=? AND testid=?", new String[] { "2,1" }); // this statement does not work How to do it?

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  • running a stored procedure inside a sql trigger

    - by Ying
    Hi all, the business logic in my application requires me to insert a row in table X when a row is inserted in table Y. Furthermore, it should only do it between specific times(which I have to query another table for). I have considered running a script every 5 minutes or so to check this, but I stumbled upon triggers and figured this might be a better way to do it. But I find the syntax for procedures a little bewildering and I keep getting an error I have no idea how to fix. Here is where I start: CREATE TRIGGER reservation_auto_reply AFTER INSERT ON reservation FOR EACH ROW BEGIN IF NEW.sent_type = 1 /* In-App */ THEN INSERT INTO `messagehistory` (`trip`, `fk`, `sent_time`, `status`, `message_type`, `message`) VALUES (NEW.trip, NEW.psk, 'NOW()', 'submitted', 4, 'This is an automated reply to reservation'); END; I get an error in the VALUES part of the statmenet but im not sure where. I still have to query the other table for the information I need, but I can't even get past this part. Any help is appreciated, including links to many examples..Thanks

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  • How to check if a child-object is populated

    - by TheQ
    How can i check if a child-object of a linq-object is populated or not? Example code below. My model have two methods, one joins data, and the other does not: public static Member GetMemberWithPhoto(Guid memberId) { using (DataContext db = new DataContext()) { DataLoadOptions dataLoadOptions = new DataLoadOptions(); dataLoadOptions.LoadWith<Member>(x => x.UserPhoto); db.LoadOptions = dataLoadOptions; var query = from x in db.Members where x.MemberId == memberId select x; return query.FirstOrDefault(); } } public static Member GetMember(Guid memberId) { using (DataContext db = new DataContext()) { var query = from x in db.Members where x.MemberId == memberId select x; return query.FirstOrDefault(); } } Then my control have the following code: Member member1 = Member.GetMemberWithPhoto(memberId); Member member2 = Member.GetMember(memberId); Debug.WriteLine(member1.UserPhoto.ToString()); Debug.WriteLine(member2.UserPhoto.ToString()); The last line will generate a "Cannot access a disposed object" exception. I know that i can get rid of that exception just by not disposing the datacontext, but then the last line will generate a new query to the database, and i don't want that. What i would like is something like: Debug.WriteLine((member1.UserPhoto.IsPopulated()) ? member1.UserPhoto.ToString() : "none"); Debug.WriteLine((member2.UserPhoto.IsPopulated()) ? member2.UserPhoto.ToString() : "none"); Is it possible?

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  • Select count() max() Date HELP!!! mysql oracle

    - by DAVID
    Hi guys i have a table with shifts history along with emp ids im using this code to retrieve a list of employees and their total shifts by specifying the range to count from: SELECT ope_id, count(ope_id) FROM operator_shift WHERE ope_shift_date >=to_date( '01-MAR-10','dd-mon-yy') and ope_shift_date <= to_date('31-MAR-10','dd-mon-yy') GROUP BY OPE_ID which gives OPE_ID COUNT(OPE_ID) 1 14 2 7 3 6 4 6 5 2 6 5 7 2 8 1 9 2 10 4 10 rows selected. NOW how do i choose the employee with the highest no of shifts under the specified range date, please this is really important

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  • Transaction within IF THEN ELSE doesn't commit

    - by boris callens
    In my TSQL script I have an IF THEN ELSE structure that checks if a column already exists. If not it creates the column and updates it. IF NOT EXISTS( SELECT 1 FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'tableName' AND COLUMN_NAME = 'columnName')) BEGIN BEGIN TRANSACTION ALTER TABLE tableName ADD columnName int NULL COMMIT BEGIN TRANSACTION update tableName set columnName = [something] from [subquery] COMMIT END This doesn't work because the column doesn't exist after the commit. Why doesn't the COMMIT commit?

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  • Optimize SQL query (Facebook-like application)

    - by fabriciols
    My application is similar to Facebook, and I'm trying to optimize the query that get user records. The user records are that he as src ou dst. The src is in usermuralentry directly, the dst list are in usermuralentry_user. So, a entry can have one src and many dst. I have those tables: mysql> desc usermuralentry ; +-----------------+------------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-----------------+------------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | user_src_id | int(11) | NO | MUL | NULL | | | private | tinyint(1) | NO | | NULL | | | content | longtext | NO | | NULL | | | date | datetime | NO | | NULL | | | last_update | datetime | NO | | NULL | | +-----------------+------------------+------+-----+---------+----------------+ 10 rows in set (0.10 sec) mysql> desc usermuralentry_user ; +-------------------+---------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------------+---------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | usermuralentry_id | int(11) | NO | MUL | NULL | | | userinfo_id | int(11) | NO | MUL | NULL | | +-------------------+---------+------+-----+---------+----------------+ 3 rows in set (0.00 sec) And the following query to retrieve information from two users. mysql> explain SELECT * FROM usermuralentry AS a , usermuralentry_user AS b WHERE a.user_src_id IN ( 1, 2 ) OR ( a.id = b.usermuralentry_id AND b.userinfo_id IN ( 1, 2 ) ); +----+-------------+-------+------+-------------------------------------------------------------------------------------------+------+---------+------+---------+------------------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+------+-------------------------------------------------------------------------------------------+------+---------+------+---------+------------------------------------------------+ | 1 | SIMPLE | b | ALL | usermuralentry_id,usermuralentry_user_bcd7114e,usermuralentry_user_6b192ca7 | NULL | NULL | NULL | 147188 | | | 1 | SIMPLE | a | ALL | PRIMARY | NULL | NULL | NULL | 1371289 | Range checked for each record (index map: 0x1) | +----+-------------+-------+------+-------------------------------------------------------------------------------------------+------+---------+------+---------+------------------------------------------------+ 2 rows in set (0.00 sec) but it is taking A LOT of time... Some tips to optimize? Can the table schema be better in my application?

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  • Multiple ID's in database

    - by eric
    I have a database that contains a few tables such as person, staff, member, and supporter. The person table contains information about every staff, member, and supporter. The information it contains is name,address,email, and telephone. I also created an id that is the primary key. My issue is that I also have an primary key ID for staff, member, and supporter. For instance, in the person table is John with id 1. He is a supporter so in the supporter table is pID(for person id)to reference back to John with all his information and ID(for supporter ID). pID references to the person table and every person has an ID incremented by 1 starting at 1. supporter ID is for every supporter and also starts at 1 and is incremented by 1. Is it possible to have in the supporter table pID = 1 and supporter ID = 1? Another person may have a pID = 26 and supporter ID = 5. Or will supporter ID have to be different than the pID and be something like "sup"? So you would have pID = 1 and supporter ID = sup1 or pID = 26 and supporter ID = sup5

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  • MySQL - Find entries that refer to a specified index.

    - by Conor H
    Hi, So I have a booking system where I have a 'lesson_type' table with 'lesson_type_id' as PK. I have a constraint in place here so I can't delete a lesson_type if there are bookings made for that lesson_type. I would like to be able to determine if this lesson_type_id is being referred to by any entries in the bookings table (or any other table for that matter) so I can notify the user gracefully. i.e. not have a mysql error be thrown when they try and delete a record. What kind of query would I use for this? Thanks.

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  • error in fill datagrid whit query

    - by Amir Tavakoli
    i have a data-gride-view and i add my query to this when write my query i catch this error: The schema returned by the new query differs from the base query and this my query: SELECT B.SettingKey, 'SysSettingsDep' AS TableName, B.SettingValue, B.SettingDesc FROM SysCustomer AS A INNER JOIN SysSettingsDep AS B ON A.SettingKey = B.SettingKey UNION SELECT C.SettingKey, 'SysSettingsMachine' AS TableName, C.SettingValue, C.SettingDesc FROM SysCustomer AS A INNER JOIN SysSettingsMachine AS C ON A.SettingKey = C.SettingKey UNION SELECT D.SettingKey, 'SysSettings' AS TableName, D.SettingValue, D.SettingDesc FROM SysCustomer AS A INNER JOIN SysSettings AS D ON A.SettingKey = D.SettingKey help me to solve this, tnx

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  • How to select a subset of results from a select statement

    - by Ankur
    I have a table that stores RDF triples: triples(triple_id, sub_id, pre_id, obj_id) The method (I need to write) will receive an array of numbers which correspond to pre_id values. I want to select all sub_id values that have a corresponding pre_id for all the pre_ids in the array that is passed in. E.g. if I had a single pre_id values passed in... lets call the value passed in preId, I would do: select sub_id from triples where pre_id=preId; However since I have mutliple pre_id values I want to keep iterating through the pre_id values and only keep the sub_id values corresponding to the "triples" records that have both. E.g. image there are five records: triples(1, 34,65,23) triples(2, 31,35,28) triples(3, 32,32,19) triples(4, 12,65,28) triples(5, 76,32,34) If I pass in an array of pre_id values [65,32] then I want to select the first, third, fourth and fifth records. What would I do for that?

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  • Entity Framework EntityKey / Foreign Key problem.

    - by Ronny176
    Hi, I keep getting the same error: Entities in 'VlaamseOverheidMeterEntities.ObjectMeter' participate in the 'FK_ObjectMeter_Meter' relationship. 0 related 'Meter' were found. 1 'Meter' is expected. I have the following table structure: Meter 1 <- * ObjectMeter * - 1 VO_Object It is always the same scenario: The first meter is added to the database, the second meter gives the error above. I have the following code in my manager: public List<string> addTemporary(string username, string meterNaam, string readingType, string parentID) { Meter meter = new Meter(); VO_Object voObject = objectManager.getObjectByID(parentID); ObjectMeter objMeter = new ObjectMeter(); meter.readingType = (int)Enum.Parse(typeof(ReadingType), readingType); meter.isActive = true; meter.name = meterNaam; meter.startDate = DateTime.Now; meter.endDate = DateTime.Now.AddYears(6000); meter.uniqueIdentifier = "N/A"; meter.meterType = (int)Enum.Parse(typeof(MeterType), "NA"); meter.meterCategory = (int)Enum.Parse(typeof(MeterCategory), "NA"); meter.energyType = (int)Enum.Parse(typeof(EnergyType), "NA"); meter.utilityType = (int)Enum.Parse(typeof(UtilityType), "NA"); meter.unitOfMeasure = (int)Enum.Parse(typeof(UnitOfMeasure), "NA"); objMeter.valid_from = meter.startDate; objMeter.valid_until = meter.endDate; objMeter.Meter = meter; objMeter.VO_Object = voObject; createMeter(meter); List<String> str = new List<string>(); str.Add("" + meter.meterID); str.Add(meter.name); return str; } and this in my Dao Class which links to the database: internal void CreateMeter(Meter _meter) { _entities.AddToMeter(_meter); _entities.SaveChanges(); } Can someone please explain this error? Ronald

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  • How do I all the registered users on a day report

    - by Nadal
    I have a table called users where I have two columns: name and created_at. created_at column column is of type datetime and it stores the datetime when this user was created. I need to know the number of users created for a given date range. Let's say I ask give me user report between 1-nov-2010 and 30-nov-2010 . I need something like this 1-nov-2010: 2 2-nov-2010: 5 The problem I am running into is that created_at data has value upto second. How do I check if a created_at date falls within a given date. Any help in solving this problem is appreciated. I am using mysql5.

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  • Get previous and next row from current id

    - by Hukr
    How can I do to get the next row in a table? `image_id` int(11) NOT NULL auto_increment `image_title` varchar(255) NOT NULL `image_text` mediumtext NOT NULL `image_date` datetime NOT NULL `image_filename` varchar(255) NOT NULL If the current image is 3 for example and the next one is 7 etc. this won’t work: $query = mysql_query("SELECT * FROM images WHERE image_id = ".intval($_GET['id'])); echo $_GET['id']+1; How should I do? thanks

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  • Postgres: Find table foreign keys (Faster alternative)

    - by Najera
    Is there faster alternative to this: Take almost 1 minute in our server. SELECT tc.constraint_name, tc.table_name, kcu.column_name, ccu.table_name AS foreign_table_name, ccu.column_name AS foreign_column_name FROM information_schema.table_constraints AS tc JOIN information_schema.key_column_usage AS kcu ON tc.constraint_name = kcu.constraint_name JOIN information_schema.constraint_column_usage AS ccu ON ccu.constraint_name = tc.constraint_name WHERE constraint_type = 'FOREIGN KEY' AND tc.table_name='mytable'; Maybe using pg_class metadata?, thanks.

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  • Best way to store a database password in a startup script / config file?

    - by Mark Harrison
    So our web server apps need to connect to the database, and some other apps have startup scripts that execute at boot time. What's the best way to store the name/password for these applications, in terms of security, e.g. perhaps we don't want sysadmins to know the database password maintainability, e.g. making the configuration easy to change when the password changes, etc. both windows and linux solutions appreciated!

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  • Error while converting function from oracle to mssql

    - by sss
    Hi, I am migrating a function from oracle to mssql 2008.This function raises Select statements included within a function cannot return data to a client as error.How can i solve this problem? Original PLSQL Code CREATE OR REPLACE function f_birim_cevrim_katsayi (p_ID_MAMUL in number, p_ID_BIRIMDEN in number, p_ID_BIRIME in number) return number is v_katsayi number; begin v_katsayi:=0; if p_ID_BIRIMDEN!=p_ID_BIRIME then for c in ( select * from CR_BIRIM_CEVRIM where ID_MAMUL = p_ID_MAMUL and ( (ID_BIRIM = p_ID_BIRIMDEN and ID_BIRIM2 = p_ID_BIRIME) OR ( ID_BIRIM2 = p_ID_BIRIMDEN and ID_BIRIM = p_ID_BIRIME) ) and VALID = 1) loop if c.ID_BIRIM=p_ID_BIRIMDEN then v_katsayi:=c.MT_ORAN; else v_katsayi:=1/c.MT_ORAN; end if; end loop; else v_katsayi:=1; end if; return round(v_katsayi,10); exception when others then return 0; end; TSQL CODE If Exists ( SELECT name FROM sysobjects WHERE name = 'f_birim_cevrim_katsayi' AND type = 'FN') DROP FUNCTION f_birim_cevrim_katsayi GO CREATE FUNCTION f_birim_cevrim_katsayi ( @p_ID_MAMUL FLOAT , @p_ID_BIRIMDEN FLOAT , @p_ID_BIRIME FLOAT ) RETURNS float AS BEGIN DECLARE @adv_error INT DECLARE @v_katsayi FLOAT SELECT @v_katsayi = 0 IF @p_ID_BIRIMDEN != @p_ID_BIRIME BEGIN DECLARE cursor_for_inline_select1 CURSOR LOCAL FOR SELECT * FROM CR_BIRIM_CEVRIM WHERE ID_MAMUL = @p_ID_MAMUL AND ((ID_BIRIM = @p_ID_BIRIMDEN AND ID_BIRIM2 = @p_ID_BIRIME) OR (ID_BIRIM2 = @p_ID_BIRIMDEN AND ID_BIRIM = @p_ID_BIRIME)) AND VALID = 1 OPEN cursor_for_inline_select1 FETCH NEXT FROM cursor_for_inline_select1 WHILE (@@FETCH_STATUS <> -1) BEGIN IF c.ID_BIRIM = @p_ID_BIRIMDEN BEGIN SELECT @v_katsayi = c.MT_ORAN END ELSE BEGIN SELECT @v_katsayi = 1/c.MT_ORAN END END CLOSE cursor_for_inline_select1 DEALLOCATE cursor_for_inline_select1 END ELSE BEGIN SELECT @v_katsayi = 1 END DEALLOCATE cursor_for_inline_select1 return ROUND(@v_katsayi, 10) GOTO ExitLabel1 Exception1: BEGIN DEALLOCATE cursor_for_inline_select1 return 0 END ExitLabel1: return ROUND(@v_katsayi, 10) END GO

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  • Use count or have a field that tallies?

    - by Dan LaManna
    Fairly simple concept, making an extremely basic message board system and I want users to have a post count. Now I was debating on whether or not to have a tally in their row that is added each time a post by them is created, or subtracted by one each time a post of theirs is deleted. However I'm sure that performing a count query when the post count is requested would be more accurate due to unforseen circumstances (say a thread gets deleted and it doesn't lower their tally properly), however this seems like it would be less efficient to run a query EVERY time their post count is loaded, especially in the case of them having 10 posts on the same page and it lists their post count each post. Thoughts/Advice? Thanks

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  • SimpleDB as Denormalized DB

    - by Max
    In an environment where you have a relational database which handles all business transactions is it a good idea to utilise SimpleDB for all data queries to have faster and more lightweight search? So the master data storage would be a relational DB which is "replicated"/"transformed" into SimpleDB to provide very fast read only queries since no JOINS and complicated subselects are needed.

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  • How to use value from primary accessdatasource control as parameter in select query for secondary ac

    - by weedave
    Hi, I'm trying to display all orders placed and I have a primary accessdatasource control that has a select query to get the customer information and the orderID. I want to use the orderID value from this first query as a parameter for the secondary accessdatasource control that selects the product information of the products in the order. In plain english, I want to:- select product info from product table where orderID = ? (where ? is the orderID value from the first query) I have tried the <%#Eval("OrderID")% but I get a "server tag not well formed" error, but I do get results returned when I just type the order ID in, but obviously every result (order) just contains the same product info... <asp:Repeater ID="Repeater1" runat="server" DataSourceID="AccessDataSource1"> <ItemTemplate> <asp:AccessDataSource ID="AccessDataSource2" runat="server" DataFile="~/App_Data/project.mdb" SelectCommand="SELECT orderDetails.OrderID, album.Artist, album.Album, album.Cost, album.ImageURL, orderDetails.Quantity, orderDetails.Total FROM (album INNER JOIN orderDetails ON album.AlbumID = orderDetails.AlbumID) WHERE (orderDetails.OrderID = ? )"> <SelectParameters> // Error is on this line <asp:Parameter Name="OrderID" DefaultValue="<%#Eval ("OrderID")%>" /> </SelectParameters> </asp:AccessDataSource> <div class="viewAllOrdersOrderArea"> <div class="viewAllOrdersOrderSummary"> <p><b>Order ID: </b><%#Eval("OrderID")%></p> <h4>Shipping Details</h4> <p><b>Shipping Address: </b><%#Eval("ShippingName")%>, <%#Eval("ShippingAddress")%>, <%#Eval("ShippingTown")%>, <%#Eval("ShippingPostcode")%></p> <h4>Payment Details</h4> <p><b>Cardholder's Address: </b><%#Eval("CardHolder")%>, <%#Eval("BillingAddress")%>, <%#Eval("BillingTown")%>, <%#Eval("BillingPostcode")%></p> <p><b>Payment Method: </b><%#Eval("CardType")%></p> <p><b>Card Number: </b><%#Eval("CardNumber")%></p> <p><b>Start Date: </b><%#Eval("StartDate")%>, Expiry Date: <%#Eval("ExpiryDate")%></p> <p><b>Security Digits: </b><%#Eval("SecurityDigits")%></p> <h4>Ordered items:</h4> <asp:Repeater ID="Repeater2" runat="server" DataSourceID="AccessDataSource2"> <ItemTemplate> <div style="display: block; float: left;"> <div class="viewAllOrdersProductImage"> <img width="70px" height="70px" alt="<%# Eval("Artist") %> - <%# Eval("Album") %>" src="assets/images/thumbs/<%# Eval("ImageURL") %>" /> </div> <div style="display:block; float:left; padding-top:15px; padding-right:20px;"><p><b><%# Eval("Artist") %> - <%# Eval("Album") %></b></p> <p>£<%# Eval("Cost") %> x <%# Eval("Quantity") %> = £<%#Eval("Total")%></p></div> </div> </ItemTemplate> </asp:Repeater> </div> </div> </ItemTemplate> </asp:Repeater>

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  • How can i design a DB where the user can define the fields and types of a detail table in a M-D rela

    - by Simon
    My application has one table called 'events' and each event has approx 30 standard fields, but also user defined fields that could be any name or type, in an 'eventdata' table. Users can define these event data tables, by specifying x number of fields (either text/double/datetime/boolean) and the names of these fields. This 'eventdata' (table) can be different for each 'event'. My current approach is to create a lookup table for the definitions. So if i need to query all 'event' and 'eventdata' per record, i do so in a M-D relaitionship using two queries (i.e. select * from events, then for each record in 'events', select * from 'some table'). Is there a better approach to doing this? I have implemented this so far, but most of my queries require two distinct calls to the DB - i cannot simply join my master 'events' table with different 'eventdata' tables for each record in in 'events'. I guess my main question is: can i join my master table with different detail tables for each record? E.g. SELECT E.*, E.Tablename FROM events E LEFT JOIN 'E.tablename' T ON E._ID = T.ID If not, is there a better way to design my database considering i have no idea on how many user defined fields there may be and what type they will be.

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  • Performing Inner Join for Multiple Columns in the Same Table

    - by frankiefrank
    I have a scenario which I'm a bit stuck on. Let's say I have a survey about colors, and I have one table for the color data, and another for people's answers. tbColors color_code , color_name 1 , 'blue' 2 , 'green' 3 , 'yellow' 4 , 'red' tbAnswers answer_id , favorite_color , least_favorite_color , color_im_allergic_to 1 , 1 , 2 3 2 , 3 , 1 4 3 , 1 , 1 2 4 , 2 , 3 4 For display I want to write a SELECT that presents the answers table but using the color_name column from tbColors. I understand the "most stupid" way to do it naming tbColors three times in the FROM section, using a different alias for each column to replace. How would a non-stupid way look?

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