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  • Why is selecting specified columns, and all, wrong in Oracle SQL?

    - by TomatoSandwich
    Say I have a select statement that goes.. select * from animals That gives a a query result of all the columns in the table. Now, if the 42nd column of the table animals is is_parent, and I want to return that in my results, just after gender, so I can see it more easily. But I also want all the other columns. select is_parent, * from animals This returns ORA-00936: missing expression. The same statement will work fine in Sybase, and I know that you need to add a table alias to the animals table to get it to work ( select is_parent, a.* from animals ani), but why must Oracle need a table alias to be able to work out the select?

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  • Can you use the same Enum in multiple entities in Linq-to-SQL?

    - by Mark
    In my persistence layer, I've declared a load of Enums to represent tables containing reference data (i.e. data never changes). In Linq2SQL, I am able to set the type of an entity property to an enum type and all is well, but as soon as I set a second entity's property to use the same enum type, the Code Generator (MSLinqToSQLGenerator) start generating an empty code file. I assume that MSLinqToSQLGenerator is quietly crashing. The question is why, and are there any work-arounds? Anyone else experienced this problem?

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  • Is there a standard SQL Table design for overriding 'big picture' default values with lower level de

    - by RichardHowells
    Here's an example. Suppose we are trying to calculate a service charge. Say sales in the USA attract a 10 dollar charge, sales in the UK attract a 20 dollar charge So far it's easy - we are starting to imagine a table that lists charges by country. Now lets assume that Alaska and Hawaii are treated as special cases they are both 15 dollars That suggests a table with states, Alaska and Hawaii are charged at 15, but presumably we need 48 (redundant) rows all saying 10. This gives us a maintainance problem, our user only wants to type 10 once NOT 48 times. It does not sit well with the UK either. The UK does not have states. Suppose we throw in another couple of cross cutting rules. If you order by phone there is a 10% supplement on the charge. If you order via the web there is a 10% discount. But for some reason best known to the owners of the business the web/phone supplement/discount are not applied in Hawaii. It seems to me that this is quite a common kind of problem and there is probably a well known arrangement of tables to store the data. Most cases get handled by broad brush answers, but there are some very detailed low level variations that give rise to a huge number of theoretical combinations, most of which are not used.

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  • How to insert a value based on lookup from another table [SQL]?

    - by Shaitan00
    I need to find a way to do an INSERT INTO table A but one of the values is something that comes from a lookup on table B, allow me to illustrate. I have the 2 following tables: Table A: A1: String A2: Integer value coming from table B A3: More Data Table B: B1: String B2: Integer Value Example row of A: {"Value", 101, MoreData} Example row of B: {"English", 101} Now, I know I need to INSERT the following into A {"Value2", "English", MoreData} but obviously that won't work because it is expecting an Integer in the second column not the word "English", so I need to do a lookup in Table B first. Something like this: INSERT INTO tableA (A1, A2, A3) VALUES ("Value2", SELECT B2 FROM tableB where B1="English", MoreData); Obviously this doesn't work as-is ... Any suggestions?

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  • Crash the program with cmd line args

    - by Debanjan
    Lets us consider the following program : #include <stdlib.h> int main(int argc, char **argv){ int a,b; if (argc != 3) return -1; a = atoi(argv[1]); b = atoi(argv[2]); a = b ? a/b : 0; return a; } The task is to crash the program by providing arguments in command-line.

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  • Algorithms for finding the intersections of intervals

    - by tomwu
    I am wondering how I can find the number of intervals that intersect with the ones before it. for the intervals [2, 4], [1, 6], [5, 6], [0, 4], the output should be 2. from [2,4] [5,6] and [5,6] [0,4]. So now we have 1 set of intervals with size n all containing a point a, then we add another set of intervals size n as well, and all of the intervals are to the right of a. Can you do this in O(nlgn) and O(nlg^2n)?

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  • Dynamic SQL Rows & Columns...cells require subsequent query. Best approach?

    - by Pyrrhonist
    I have the following tables below City --------- CityID StateID Name Description Reports --------- ReportID HeaderID FooterID Description I’m trying to generate a grid for use in a .Net control (Gridview, Listview…separate issue about which will be the ‘best’ one to use for my purposes) which will assign the reports as the columns and the cities as the rows. Which cities get displayed is based on the state selected, and is easy enough SELECT * FROM CITIES WHERE STATEID=@StateID However, the user is able to select which reports are being generated for each City (Demographics, Sales, Land Area, etc.). Further, the resultant cells (City * Report) is a sub-query on different tables based on the city selected and the report. Ie. Column Sales selected yields SELECT * FROM SALES WHERE CITYID=@CityID I’ve programmed a VERY inelegant solution using multiple queries and brute-forcing the grid to be created (line by line, row by row creation of data elements), but I’m positive there’s got to be a better way of accomplishing this…? Any / all suggestions appreciated here as the brute force approach I’ve gotten is slow and cumbersome…and this will have to be used often by the client, so I’m not sure it’ll be acceptable in it’s current implementation.

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  • How do I create a create and execute an SQL command using OleDB directly?

    - by Pagis
    I want to use the OleDB interfaces directly to open a connection to a DB, create a command and executing it (for example using the ICommandText interface). The main thing I can't find is how to create the connection and the command object and how to connect the object that implements the ICommandText to the connection. In ADO I would just use the ActiveConnection property but I want to do this directly on the OleDB interfaces. Also, if anyone can recommend a tutorial to OleDB, ether online or a book, free or not that would be great (but a tutorial and not just a reference / API) I'm using C++ but any native code would be fine.

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  • How to check if the sum of some records equals the difference between two other records in t-sql?

    - by Dan Appleyard
    I have a view that contains bank account activity. ACCOUNT BALANCE_ROW AMOUNT SORT_ORDER 111 1 0.00 1 111 0 10.00 2 111 0 -2.50 3 111 1 7.50 4 222 1 100.00 5 222 0 25.00 6 222 1 125.00 7 ACCOUNT = account number BALANCE_ROW = either starting or ending balance would be 1, otherwise 0 AMOUNT = the amount SORT_ORDER = simple order to return the records in the order of start balance, activity, and end balance I need to figure out a way to see if the sum of the non balance_row rows equal the difference between the ending balance and the starting balance. The result for each account (1 for yes, 0 for no) would be simply added to the resulting result set. Example: Account 111 had a starting balance of 0.00. There were two account activity records of 10.00 and -2.5. That resulted in the ending balance of 7.50. I've been playing around with temp tables, but I was not sure if there is a more efficient way of accomplishing this. Thanks for any input you may have!

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  • Is it a problem if i query again and again to SQL Server 2005 and 2000?

    - by learner
    Window app i am constructing is for very low end machines (Celeron with max 128 RAM). From the following two approaches which one is the best (I don't want that application becomes memory hog for low end machines):- Approach One:- Query the database Select GUID from Table1 where DateTime <= @givendate which is returning me more than 300 thousands records (but only one field i.e. GUID - 300 thousands GUIDs). Now running a loop to achieve next process of this software based on GUID. Second Approach:- Query the database Select Top 1 GUID from Table1 where DateTime <= @givendate with top 1 again and again until all 300 thousands records done. It will return me only one GUID at a time, and I can do my next step of operation. What do you suggest which approach will use the less Memory Resources?? (Speed / performance is not the issue here).

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  • Special simple random number generator

    - by psihodelia
    How to create a function, which on every call generates a random integer number? This number must be most random as possible (according to uniform distribution). It is only allowed to use one static variable and at most 3 elementary steps, where each step consists of only one basic arithmetic operation of arity 1 or 2. Example: int myrandom(void){ static int x; x = some_step1; x = some_step2; x = some_step3; return x; } Basic arithmetic operations are +,-,%,and, not, xor, or, left shift, right shift, multiplication and division. Of course, no rand(), random() or similar staff is allowed.

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  • SQL Server 2005: Why would a delete from a temp table hang forever?

    - by Dr. Zim
    DELETE FROM #tItem_ID WHERE #tItem_ID.Item_ID NOT IN (SELECT DISTINCT Item_ID FROM Item_Keyword JOIN Keyword ON Item_Keyword.Keyword_ID = Keyword.Record_ID WHERE Keyword LIKE @tmpKW) The Keyword is %macaroni%. Both temp tables are 3300 items long. The inner select executes in under a second. All strings are nvarchar(249). All IDs are int. Any ideas? I executed it (it's in a stored proc) for over 12 minutes without it finishing.

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  • WTF why does this SQL work in VS but not in CODE?

    - by acidzombie24
    The line cmd.ExecuteNonQuery(); cmd.CommandText CREATE TRIGGER subscription_trig_0 ON subscription AFTER INSERT AS UPDATE user_data SET msg_count=msg_count+1 FROM user_data JOIN INSERTED ON user_data.id = INSERTED.recipient; The exception: Incorrect syntax near the keyword 'TRIGGER'. Then using VS 2010, connected to the very same file (a mdf file) i run the query above and i get a success message. WTF!

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  • Are these 2 sql queries equivalent in all respects (e.g. estimated and actual execution plan)?

    - by Xerion
    Are query 1) == 2) in terms of estimated query plan AND actual plan? (can statistics affect the actual plan here, ever?) declare @cat int -- input param from prc ... 1) select * from A as a join B as b on b.id = a.id on b.cat = @cat join C as c on c.fid = b.fid on c.cat = @cat where a.cat = @cat 2) select * from A as a join B as b on b.id = a.id on b.cat = a.cat join C as c on c.fid = b.fid on c.cat = b.cat where a.cat = @cat It seems to me that these should logically be equivalent and the execution plan should always be the same regardless of actual difference in tables. And adding more conditions either in join, or where, or add more tables to join shouldn't change this. Are there cases this is not true?

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  • Shuffle array variables in a pre-specified order, without using extra memory of "size of input array"

    - by Eternal Learner
    Input : A[4] = {0,4,-1,1000} - Actual Array P[4] = {1,0,3,2} - Order to be reshuffled Output: A[4] = {4,0,1000,-1} Condition : Don't use an additional array as memory. Can use an extra variable or two. Problem : I have the below program in C++, but this fails for certain inputs of array P. #include<iostream> using namespace std; void swap(int *a_r,int *r) { int temp = *r; *r = *a_r; *a_r = temp; } int main() { int A[4] = {0,4,-1,1000}; int P[4] = {3,0,1,2}; int value = A[0] , dest = P[0]; for(int i=0; i<4;i++) { swap(&A[dest],&value); dest = P[dest]; } for(int i=0;i<4;i++) cout<<A[i]<<" "; }

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  • Add to exisiting db values, rather than overwrite - PDO

    - by sam
    Im trying to add to existing decimal value in table, for which im using the sql below: UPDATE Funds SET Funds = Funds + :funds WHERE id = :id Im using a pdo class to handle my db calls, with the method below being used to update the db, but i couldnt figure out how to amend it to output the above query, any ideas ? public function add_to_values($table, $info, $where, $bind="") { $fields = $this->filter($table, $info); $fieldSize = sizeof($fields); $sql = "UPDATE " . $table . " SET "; for($f = 0; $f < $fieldSize; ++$f) { if($f > 0) $sql .= ", "; $sql .= $fields[$f] . " = :update_" . $fields[$f]; } $sql .= " WHERE " . $where . ";"; $bind = $this->cleanup($bind); foreach($fields as $field) $bind[":update_$field"] = $info[$field]; return $this->run($sql, $bind); }

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  • MYSQL - SQL query Getting single record for the similar records and populating other columns with which has more length

    - by Bujji
    Here is my case , I have a database table with below fields name place_code email phone address details estd others and example data if you look at the above example table First three records are talking about XYZ and place code 1020 . I want create a single record for these three records based on substring(name,1,4) place_code ( I am lucky here for all the similar records satisfies this condition and unique in the table .) For the other columns which record column length has max . For example again for the above 3 records email should be [email protected] , phone should be 657890 and details should be "testdetails" This should be done for all the table . (Some has single records and some has max 10 records ) Any help on query that helps me to get the desired result ? Thank You Regards Kiran

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  • Is "campaign_$" a bad name for a SQL column?

    - by Summer
    PostgreSQL has allowed me to name a column "campaign_$". I like the name because it's short and to the point, and other potential names like "campaign_receipts" seem longer and less clear. BUT, I wonder if I'll eventually regret putting a $ symbol in a column name, either in PHP or in some other distant part of the architecture. Should I just stick to letters and underscores? Thanks!

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