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• How to save to two tables using one SQLAlchemy model

  - by Oatman

  I have an SQLAlchemy ORM class, linked to MySQL, which works great at saving the data I need down to the underlying table. However, I would like to also save the identical data to a second archive table. Here's some psudocode to try and explain what I mean my_data = Data() #An ORM Class my_data.name = "foo" #This saves just to the 'data' table session.add(my_data) #This will save it to the identical 'backup_data' table my_data_archive = my_data my_data_archive.__tablename__ = 'backup_data' session.add(my_data_archive) #And commits them both session.commit() Just a heads up, I am not interested in mapping a class to a JOIN, as in: http://www.sqlalchemy.org/docs/05/mappers.html#mapping-a-class-against-multiple-tables

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• displaying multiple values with .FIELDS adodb

  - by every_answer_gets_a_point

  i am getting some data: rs.Filter = "datapath='" + dpath + "' and analystname='" + aname + "' and reportname='" + rname + "' and batchstate='" + bstate + "'" If Not rs.EOF Then MsgBox rs.Fields("rowid") End If if the rs.filter returns multiple records, how do i get rs.fields("rowid") to give me multiple rowid values?

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• LINQ2SQL:Calling Stored procedure and reading return value

  - by Shyju

  Using LINQ 2SQL , How can i call a stored procedure which returns either 1 or 0 when being executed.My procedure has 3 input params.I want to know the return value from procedure in my code too.

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• How to get common field in ten tables with different field name

  - by Fero

  Hi all, I am having a common field in ten tables with different field name. example: table1: t1_id     t1_location 1         india 2         china 3         america table2: t2_id     t2_location 4         london 5         australia 6         america Now my o/p should be: location india china america london australia How should i get that using mysql query. thanks in advance

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• Merging rows with uniqueness constraints

  - by Flambino

  I've got a little time-tracking web app (implemented in Rails 3.2.8 & MySQL). The app has several users who add their time to specific tasks, on a given date. The system is set up so a user can only have 1 time entry (i.e. row) per task per date. I.e. if you add time twice on the same task and date, it'll add time to the existing row, rather than create a new one. Now I'm looking to merge 2 tasks. In the simplest terms, merging task ID 2 into task ID 1 would take this time | user_id | task_id | date ------+----------+----------+----------- 10 | 1 | 1 | 2012-10-29 15 | 2 | 1 | 2012-10-29 10 | 1 | 2 | 2012-10-29 5 | 3 | 2 | 2012-10-29 and change it into this time | user_id | task_id | date ------+----------+----------+----------- 20 | 1 | 1 | 2012-10-29 <-- time values merged (summed) 15 | 2 | 1 | 2012-10-29 <-- no change 5 | 3 | 1 | 2012-10-29 <-- task_id changed (no merging necessary) I.e. merge by summing the time values, where the given user_id/date/task combo would conflict. I figure I can use a unique constraint to do a ON DUPLICATE KEY UPDATE ... if I do an insert for every task_id=2 entry. But that seems pretty inelegant. I've also tried to figure a way to first update all the rows in task 1 with the summed-up times, but I can't quite figure that one out. Any ideas?

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• Foreach loop problem for Iqueyable object

  - by Vikas

  Hi, Can we use foreach loop for Iqueryable object? I'd like to do something as follow: query = Iqueryable<Myclass> = objDataContext.Myclass; // objDataContext is an object of LINQ datacontext class int[] arr1 = new int[] { 3, 4, 5 }; foreach (int i in arr1) { query = query.Where(q => (q.f_id1 == i || q.f_id2 == i || q.f_id3 == i)); } It gives me wrong output as each time value if i is changed.

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• “Function” calling inside store procedure

  - by idimba

  Hi, I have a big store procedure, that contains a lot of INSERTs. There're many INSERTS that almost identical - they're different by some parameter(s) (all INSERTs to the same table) Is there a way to create a function/method, to which I'll pass the above parameter(s) and the function/method will generate concrete INSERT's? Thanks

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• How to output multiple rows from an SQL query using the mysqli object

  - by Jonathan

  Assuming that the mysqli object is already instantiatied (and connected) with the global variable $mysql, here is the code I am trying to work with. class Listing { private $mysql; function getListingInfo($l_id = "", $category = "", $subcategory = "", $username = "", $status = "active") { $condition = "`status` = '$status'"; if (!empty($l_id)) $condition .= "AND `L_ID` = '$l_id'"; if (!empty($category)) $condition .= "AND `category` = '$category'"; if (!empty($subcategory)) $condition .= "AND `subcategory` = '$subcategory'"; if (!empty($username)) $condition .= "AND `username` = '$username'"; $result = $this->mysql->query("SELECT * FROM listing WHERE $condition") or die('Error fetching values'); $this->listing = $result->fetch_array() or die('could not create object'); foreach ($this->listing as $key => $value) : $info[$key] = stripslashes(html_entity_decode($value)); endforeach; return $info; } } there are several hundred listings in the db and when I call $result-fetch_array() it places in an array the first row in the db. however when I try to call the object, I can't seem to access more than the first row. for instance: $listing_row = new Listing; while ($listing = $listing_row-getListingInfo()) { echo $listing[0]; } this outputs an infinite loop of the same row in the db. Why does it not advance to the next row? if I move the code: $this->listing = $result->fetch_array() or die('could not create object'); foreach ($this->listing as $key => $value) : $info[$key] = stripslashes(html_entity_decode($value)); endforeach; if I move this outside the class, it works exactly as expected outputting a row at a time while looping through the while statement. Is there a way to write this so that I can keep the fetch_array() call in the class and still loop through the records?

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• Database select * for a Noob

  - by Kevin Brown

  I've heard that it's bad to select all the fields in a database. Is this true, and if so, why?

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• Should I Use GUID or IDENTITY as Thread Number?

  - by user311509

  offerID is the thread # which represents the thread posted. I see in forums posts are represented by random numbers. Is this achieved by IDENTITY? If not, please advice. nvarchar(max) will carry all kind of texts along with HTML tags. CREATE TABLE Offer ( offerID int IDENTITY (4382,15) PRIMARY KEY, memberID int NOT NULL REFERENCES Member(memberID), title nvarchar(200) NOT NULL, thread nvarchar(max) NOT NULL, . . . );

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• Is this use of PreparedStatements in a Thread in JAVA correct?

  - by Gormcito

  I'm still an undergrad just working part time and so I'm always trying to be aware of better ways to do things. Recently I had to write a program for work where the main thread of the program would spawn "task" threads (for each db "task" record) which would perform some operations and then update the record to say that it has finished. Therefore I needed a database connection object and PreparedStatement objects in or available to the ThreadedTask objects. This is roughly what I ended up writing, is creating a PreparedStatement object per thread a waste? I thought static PreparedStatments could create race conditions... Thread A stmt.setInt(); Thread B stmt.setInt(); Thread A stmt.execute(); Thread B stmt.execute(); A´s version never gets execed.. Is this thread safe? Is creating and destroying PreparedStatement objects that are always the same not a huge waste? public class ThreadedTask implements runnable { private final PreparedStatement taskCompleteStmt; public ThreadedTask() { //... taskCompleteStmt = Main.db.prepareStatement(...); } public run() { //... taskCompleteStmt.executeUpdate(); } } public class Main { public static final db = DriverManager.getConnection(...); }

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• get n records at a time from a temporary table

  - by Claudiu

  I have a temporary table with about 1 million entries. The temporary table stores the result of a larger query. I want to process these records 1000 at a time, for example. What's the best way to set up queries such that I get the first 1000 rows, then the next 1000, etc.? They are not inherently ordered, but the temporary table just has one column with an ID, so I can order it if necessary. I was thinking of creating an extra column with the temporary table to number all the rows, something like: CREATE TEMP TABLE tmptmp AS SELECT ##autonumber somehow##, id FROM .... --complicated query then I can do: SELECT * FROM tmptmp WHERE autonumber>=0 AND autonumber < 1000 etc... how would I actually accomplish this? Or is there a better way? I'm using Python and PostgreSQL.

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• What is your reporting tool of choice?

  - by jms

  Every project invariably needs some type of reporting functionality. From a foreach loop in your language of choice to a full blow BI platform. To get the job done what tools, widgets, platforms has the group used with success, frustration and failure?

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• MySQL Limiting a query to one consistent value

  - by Lucas Matos

  My current query returns a table like: +------------+ value1 | .... value1 | .... value2 | .... value3 | .... +------------+ I want: +------------+ value1 | .... value1 | .... +------------+ I want to only receive all rows with the first value. Normally I would do a WHERE clause if I knew that value, and I cannot use a LIMIT because each value has a different number of rows. Right now My query looks like "SELECT u.*, n.something, w.* FROM ... AS u, ... AS n, ... AS w WHERE u.id = n.id AND w.val = n.val AND u.desc LIKE '%GET REQUEST VARIABLE%';" This works great, except I get way too many rows and using PHP to do this ruins code portability and is superfluous. Thanks for reading

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• Oracle: how to UPSERT (update or insert into a table?)

  - by Mark Harrison

  The UPSERT operation either updates or inserts a row in a table, depending if the table already has a row that matches the data: if table t has a row exists that has key X: update t set mystuff... where mykey=X else insert into t mystuff... Since Oracle doesn't have a specific UPSERT statement, what's the best way to do this?

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• MYSQL to UPDATE table if row with 2 specific columns exist or INSERT new row if it does not exist

  - by user2509541

  I have a MYSQL table that looks as follows: id id_jugador id_partido team1 team2 1 2 1 5 2 2 2 2 1 1 3 1 2 0 0 I need to create a query to either INSERT new rows in the table or UPDATE the table. The condition is based on id_jugador and id_partido, meaning that if I wanted to insert id_jugador = 2 and id_partido = 1, then it should just UPDATE the existing row with the new team1 and team2 values I am sending. And dont duplicate the row. However, if I have an entry id_jugador=2 and id_partido=3, since this combination does not exist yet, it should add the new row. I read about the REPLACE INTO but it seems to be unable to check combination of UNIQUE KEYS.

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• help with delete where not in query

  - by kralco626

  I have a lookup table (##lookup). I know it's bad design because I'm duplicating data, but it speeds up my queries tremendously. I have a query that populates this table insert into ##lookup select distinct col1,col2,... from table1...join...etc... I would like to simulate this behavior: delete from ##lookup insert into ##lookup select distinct col1,col2,... from table1...join...etc... This would clearly update the table correctly. But this is a lot of inserting and deleting. It messes with my indexes and locks up the table for selecting from. This table could also be updated by something like: delete from ##lookup where not in (select distinct col1,col2,... from table1...join...etc...) insert into ##lookup (select distinct col1,col2,... from table1...join...etc...) except if it is already in the table The second way may take longer, but I can say "with no lock" and I will be able to select from the table. Any ideas on how to write the query the second way?

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• Replace always replacing null values

  - by Mike

  Why does left(FIELD, replace(nullif(charindex('-', FIELD), 0), null, len(FIELD))) always return null? The idea behind the query is that if charindex() returns 0, then convert the results into null, then convert the null into the length of the field. So if '-' does not exist, show the whole string. For some reason it makes every row equal null. Thank you.

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• Is there a better way to do updates in LinqToSQL?

  - by Vaccano

  I have a list (that comes to my middleware app from the client) that I need to put in my database. Some items in the list may already be in the db (just need an update). Others are new inserts. This turns out to be much harder than I thought I would be. Here is my code to do that. I am hoping there is a better way: public void InsertClients(List<Client> clients) { var comparer = new LambdaComparer<Client>((x, y) => x.Id == y.Id); // Get a listing of all the ones we will be updating var alreadyInDB = ctx.Clients .Where(client => clients.Contains(client, comparer)); // Update the changes for those already in the db foreach (Client clientDB in alreadyInDB) { var clientDBClosure = clientDB; Client clientParam = clients.Find(x => x.Id == clientDBClosure.Id); clientDB.ArrivalTime = clientParam.ArrivalTime; clientDB.ClientId = clientParam.ClientId; clientDB.ClientName = clientParam.ClientName; clientDB.ClientEventTime = clientParam.ClientEventTime; clientDB.EmployeeCount = clientParam.EmployeeCount; clientDB.ManagerId = clientParam.ManagerId; } // Get a list of all clients that are not in my the database. var notInDB = clients.Where(x => alreadyInDB.Contains(x, comparer) == false); ctx.Clients.InsertAllOnSubmit(notInDB); ctx.SubmitChanges(); } This seems like a lot of work to do a simple update. But maybe I am just spoiled. Anyway, if there is a easier way to do this please let me know. Note: If you are curious the code to the LambdaComparer is here: http://gist.github.com/335780#file_lambda_comparer.cs

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• Creating temporary tables in MySQL Stored Procedure

  - by burntblark

  The following procedure gives me an error when I invoke it using the CALL statement: CREATE DEFINER=`user`@`localhost` PROCEDURE `emp_performance`(id VARCHAR(10)) BEGIN DROP TABLE IF EXISTS performance; CREATE TABLE performance AS SELECT time_in, time_out, day FROM attendance WHERE employee_id = id; END The error says "Unknown table 'performance' ". This is my first time actually using stored procedures and I got my sources from Google. I just cant figure out what I am doing wrong.

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• Query with multiple IN-statements but without the cartesian product

  - by Janne

  How could I make this kind of query e.g. in MySQL SELECT * FROM Table t WHERE t.a IN (1,2,3) AND t.b IN (4,5,6) AND t.c IN (7,8,9) ... so that the result would contain only the three rows: t.a|t.b|t.c ---+---+--- 1 | 4 | 7 2 | 5 | 8 3 | 6 | 9 The above query of course returns all the combinations of the values in the IN clauses but I would like to get just the ones where the first elements of each tuple match, second elements of each tuple match and so on. Is there any efficient way to do this? By the way is there some common term for this kind of query or concept? I'm having hard time coming up with the question's title because I can't put this into words..

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• WHERE condition accross multiple rows

  - by Chris G

  I have this table... -------------------------------------- | user_id | status | status_date | -------------------------------------- | 1 | Current | 2012-08-01 | | 1 | Referral | 2012-03-14 | | 2 | Referral | 2012-04-23 | | | | | -------------------------------------- How would I query to find a distinct user_id who has a referral date before 2012-06-30 AND either a current date of after 2012-06-30 or no current status record at all? Database is MySQL.

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• Help Me With This MS-Access Query

  - by yae

  I have 2 tables: "products" and "pieces" PRODUCTS idProd product price PIECES id idProdMain idProdChild quant idProdMain and idProdChild are related with the table: "products". Other considerations is that 1 product can have some pieces and 1 product can be a piece. Price product equal a sum of quantity * price of all their pieces. "Products" table contains all products (p EXAMPLE: TABLE PRODUCTS (idProd - product - price) 1 - Computer - 300€ 2 - Hard Disk - 100€ 3 - Memory - 50€ 4 - Main Board - 100€ 5 - Software - 50€ 6 - CDroms 100 un. - 30€ TABLE PIECES (id - idProdMain - idProdChild - Quant.) 1 - 1 - 2 - 1 2 - 1 - 3 - 2 3 - 1 - 4 - 1 WHAT I NEED? I need update the price of the main product when the price of the product child (piece) is changed. Following the previous example, if I change the price of this product "memory" (is a piece too) to 60€, then product "Computer" will must change his price to 320€ How I can do it using queries? Already I have tried this to obtain the price of the main product, but not runs. This query not returns any value: SELECT Sum(products.price*pieces.quant) AS Expr1 FROM products LEFT JOIN pieces ON (products.idProd = pieces.idProdChild) AND (products.idProd = pieces.idProdChild) AND (products.idProd = pieces.idProdMain) WHERE (((pieces.idProdMain)=5)); MORE INFO The table "products" contains all the products to sell that it is in the shop. The table "pieces" is to take a control of the compound products. To know those who are the products children. For example of compound product: computers. This product is composed by other products (motherboard, hard disk, memory, cpu, etc.)

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• How to not add values from Join

  - by nCdy

  SELECT ... FROM [Rep_GroupNode] C left join (SELECT .... if I'm using left join only for compare some thing due selecting how to not add(double) values from join ?

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• ora-30926 error

  - by user1331181

  I am trying to execute the following merge statement but is is showing me ora-30926 error merge into test_output target_table USING (SELECT c.test_code, c.v_report_id, upper_score, CASE WHEN c.test_code = 1 THEN b.mean_diff WHEN c.test_code = 2 THEN b.norm_dist WHEN c.test_code = 3 THEN b.ks_stats WHEN c.test_code = 4 THEN b.ginni WHEN c.test_code = 5 THEN b.auroc WHEN c.test_code = 6 THEN b.info_stats WHEN c.test_code = 7 THEN b.kl_stats END val1 FROM combined_approach b inner join test_output c on b.v_report_id = c.v_report_id and c.upper_score = b.band_code WHERE c.v_report_id = lv_report_id ORDER BY c.test_code) source_table on(target_table.v_report_id = source_table.v_report_id and target_table.v_report_id = lv_report_id) when matched then update SET target_table.upper_value = source_table.val1;

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