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  • Fill data gaps - UNION, PARTITION BY, or JOIN?

    - by Dave Jarvis
    Problem There are data gaps that need to be filled. Would like to avoid UNION or PARTITION BY if possible. Query Statement The select statement reads as follows: SELECT count( r.incident_id ) AS incident_tally, r.severity_cd, r.incident_typ_cd FROM report_vw r GROUP BY r.severity_cd, r.incident_typ_cd ORDER BY r.severity_cd, r.incident_typ_cd Data Sources The severity codes and incident type codes are from: severity_vw incident_type_vw The columns are: incident_tally severity_cd incident_typ_cd Actual Result Data 36 0 ENVIRONMENT 1 1 DISASTER 27 1 ENVIRONMENT 4 2 SAFETY 1 3 SAFETY Required Result Data 36 0 ENVIRONMENT 0 0 DISASTER 0 0 SAFETY 27 1 ENVIRONMENT 0 1 DISASTER 0 1 SAFETY 0 2 ENVIRONMENT 0 2 DISASTER 4 2 SAFETY 0 3 ENVIRONMENT 0 3 DISASTER 1 3 SAFETY Question How would you use UNION, PARTITION BY, or LEFT JOIN to fill in the zero counts?

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  • Select *, max(date) works in phpMyAdmin but not in my code

    - by kdobrev
    OK, my statement executes well in phpMyAdmin, but not how I expect it in my php page. This is my statement: SELECT egid , group_name , limit , MAX( date ) FROM employee_groups GROUP BY egid ORDER BY egid DESC ; This is may table: CREATE TABLE employee_groups ( egid int(10) unsigned NOT NULL, date date NOT NULL, group_name varchar(50) NOT NULL, limit smallint(5) unsigned NOT NULL, PRIMARY KEY (egid,date) ) ENGINE=MyISAM DEFAULT CHARSET=cp1251; I want to extract the most recent list of groups, e.g. if a group has been changed I want to have only the last change. And I need it as a list (all groups).

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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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  • Stop invalid data in a attribute with foreign key constraint using triggers?

    - by Eternal Learner
    How to specify a trigger which checks if the data inserted into a tables foreign key attribute, actually exists in the references table. If it exist no action should be performed , else the trigger should delete the inserted tuple. Eg: Consider have 2 tables R(A int Primary Key) and S(B int Primary Key , A int Foreign Key References R(A) ) . I have written a trigger like this : Create Trigger DelS BEFORE INSERT ON S FOR EACH ROW BEGIN Delete FROM S where New.A <> ( Select * from R;) ); End; I am sure I am making a mistake while specifying the inner sub query within the Begin and end Blocks of the trigger. My question is how do I make such a trigger ?

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  • How to check with PHP does a SQL database already have

    - by Dan Horvat
    I've tried to find the answer to this question but none of the answers fit. I have two databases, one has 15.000.000 entries and I want to extract the necessary data and store it in a much smaller database with around 33.000 entries. Both databases are open at the same time. Or at least they should be. While having the big database open and extracting the entries from it, is it possible to check whether the value already exists in the smaller database? I just need some generic way which checks that.

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  • How to get details about the DTS Step in a running job?

    - by vikasde
    I have scheduled a DTS to run from a scheduled job. The DTS has several steps in it. Now whenever the job is running and I take a look at the jobs section in Enterprise manager, then it always displays the following in the status: Executing Job Step 1'.... although its running all steps properly. How do I know at what step the DTS is running at?

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  • PHP - SQL query to get update time from table status

    - by Tribalcomm
    This is my php code (I already have a connection to the db): $array = mysql_query("SHOW TABLE STATUS FROM mytable;"); while ($array = mysql_fetch_array($result)) { $updatetime = $array['Update_time']; } echo $updatetime; I get: Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource. I am running MySQL 5.0.89 and PHP5. I do not want to add a new field to the table... I want to use the table status... Any help? Thanks!

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  • How to use SQL trigger to record the affected column's row number

    - by Freeman
    I want to have an 'updateinfo' table in order to record every update/insert/delete operations on another table. In oracle I've written this: CREATE TABLE updateinfo ( rnumber NUMBER(10), tablename VARCHAR2(100 BYTE), action VARCHAR2(100 BYTE), UPDATE_DATE date ) DROP TRIGGER TRI_TABLE; CREATE OR REPLACE TRIGGER TRI_TABLE AFTER DELETE OR INSERT OR UPDATE ON demo REFERENCING NEW AS NEW OLD AS OLD FOR EACH ROW BEGIN if inserting then insert into updateinfo(rnumber,tablename,action,update_date ) values(rownum,'demo', 'insert',sysdate); elsif updating then insert into updateinfo(rnumber,tablename,action,update_date ) values(rownum,'demo', 'update',sysdate); elsif deleting then insert into updateinfo(rnumber,tablename,action,update_date ) values(rownum,'demo', 'delete',sysdate); end if; -- EXCEPTION -- WHEN OTHERS THEN -- Consider logging the error and then re-raise -- RAISE; END TRI_TABLE; but when checking updateinfo, all rnumber column is zero. is there anyway to retrieve the correct row number?

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  • advanced select in Stored Procedure

    - by Auro
    Hey i got this Table: CREATE TABLE Test_Table ( old_val VARCHAR2(3), new_val VARCHAR2(3), Updflag NUMBER, WorkNo NUMBER ); and this is in my Table: INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('1',' 20',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('2',' 20',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('2',' 30',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('3',' 30',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('4',' 40',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('4',' 40',0,0); now my Table Looks like this: Row Old_val New_val Updflag WorkNo 1 '1' ' 20' 0 0 2 '2' ' 20' 0 0 3 '2' ' 30' 0 0 4 '3' ' 30' 0 0 5 '4' ' 40' 0 0 6 '5' ' 40' 0 0 (if the value in the new_val column are same then they are together and the same goes to old_val) so in the example above row 1-4 are together and row 5-6 at the moment i have in my Stored Procedure a cursor: SELECT t1.Old_val, t1.New_val, t1.updflag, t1.WorkNo FROM Test_Table t1 WHERE t1.New_val = ( SELECT t2.New_val FROM Test_Table t2 WHERE t2.Updflag = 0 AND t2.Worknr = 0 AND ROWNUM = 1 ) the output is this: Row Old_val New_val Updflag WorkNo 1 1 20 0 0 2 2 20 0 0 my Problem is, i dont know how to get row 1 to 4 with one select. (i had an idea with 4 sub-querys but this wont work if its more data that matches together) does anyone of you have an idea?

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  • Double Inner Join generates unexpected error

    - by Itamar Marom
    In my database I have three tables: Users: UserID (Auto Numbering), UserName, UserPassword and a few other unimportant fields. PrivateMessages: MessageID (Auto Numbering), SenderID and a few other fields defining the message content. MessageStatus: MessageID, ReceiverID, MessageWasRead (Boolean) What I need is a query to which I input a user's id and I get all the private messages he has received. In addition, I also need to receive each message's sender UserName. For this I wrote the following query: SELECT Users.*, PrivateMessages.*, MessageStatus.* FROM PrivateMessages INNER JOIN Users ON PrivateMessages.SenderID = Users.UserID INNER JOIN MessageStatus ON PrivateMessages.MessageID = MessageStatus.MessageID WHERE MessageStatus.ReceiverID=[@userid]; But for some reason when I try saving it in my Access database, I get the following error (translated to English by me, since my office is in a different language): Syntax error (missing operator) at expression: "PrivateMessages.SenderID = Users.UserID INNER JOIN MessageStatus ON PrivateMessages.MessageID = MessageStatus.MessageI". Any ideas what could cause this? Thanks.

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  • SqlException: Login failed for user

    - by Younes
    I use a dbml for my Data Access Layer to provide the data that i need in my app. When i connect from the server explorer everything seems fine. I choose to use my windows authentication and the connection test shows everything works just fine. When i Build my solution and run it on my IIS it says that i'm using a login that is not working. How to solve this issue?

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  • Best way to model Customer <--> Address

    - by Jen
    Every Customer has a physical address and an optional mailing address. What is your preferred way to model this? Option 1. Customer has foreign key to Address Customer (id, phys_address_id, mail_address_id) Address (id, street, city, etc.) Option 2. Customer has one-to-many relationship to Address, which contains a field to describe the address type Customer (id) Address (id, customer_id, address_type, street, city, etc.) Option 3. Address information is de-normalized and stored in Customer Customer (id, phys_street, phys_city, etc. mail_street, mail_city, etc.) One of my overriding goals is to simplify the object-relational mappings, so I'm leaning towards the first approach. What are your thoughts?

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  • Best indexing strategy for several varchar columns in Postgres

    - by Corey
    I have a table with 10 columns that need to be searchable (the table itself has about 20 columns). So the user will enter query criteria for at least one of the columns but possibly all ten. All non-empty criteria is then put into an AND condition Suppose the user provided non-empty criteria for column1 and column4 and column8 the query would be: select * from the_table where column1 like '%column1_query%' and column4 like '%column4_query%' and column8 like '%column8_query%' So my question is: am I better off creating 1 index with 10 columns? 10 indexes with 1 column each? Or do I need to find out what sets of columns are queried together frequently and create indexes for them (an index on cols 1,4 and 8 in the case above). If my understanding is correct a single index of 10 columns would only work effectively if all 10 columns are in the condition. Open to any suggestions here, additionally the rowcount of the table is only expected to be around 20-30K rows but I want to make sure any and all searches on the table are fast. Thanks!

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  • MySQL Query involving column names containing math operators

    - by devil_fingers
    I'm a MySQL scrub, and I have asked around and checked around the internet for what I'm sure will turn out to be something obvious, but I'm very frustrated with what I thought would be a very, very simple query not working. So here goes. Please be gentle. Basically, in a large database, some of the column names contain mathematical operators like "/" and "+." (Don't ask, it's not my database, I can't do anything about it). Here is the "essence" of my query (I took out the irrelevant stuff for the sake of this question): SELECT PlayerId, Season, WPA/LI AS WPALI FROM tht.stats_batting_master WHERE Season = "2010" AND teamid > 0 AND PA >= 502 GROUP BY playerid ORDER BY WPALI DESC When I run this, it returns "Unknown column 'LI' in 'field list'," I assume because it sees the "/" in WPA/LI as a division sign. Like I said, I'm sure this is easy enough to work around (it must be given how much this database is used), but I haven't' been able to figure out how. Thanks in advance for any help.

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  • explain these select statements!

    - by user329820
    Hi, I can not get the difference betwwn these statements? would you please help me,I have read some sample of select statements but I did not get these ones. SELECT 'B' FROM T WHERE A = (SELECT NULL); SELECT 'C' FROM T WHERE A = ANY (SELECT NULL); SELECT 'D' FROM T WHERE A = A; I use MySQL

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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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  • How To Join Tables from Two Different Contexts with LINQ2SQL?

    - by RSolberg
    I have 2 data contexts in my application (different databases) and need to be able to query a table in context A with a right join on a table in context B. How do I go about doing this in LINQ2SQL? Why?: We are using a SaaS product for tracking our time, projects, etc. and would like to send new service requests to this product to prevent our team from duplicating data entry. Context A: This db stores service request information. It is a third party DB and we are not able to make changes to the structure of this DB as it could have unintended non-supportable consequences downstream. Context B: This data stores the "log" data of service requests that have been processed. My team and I have full control over this DB's structure, etc. Unprocessed service requests should find their way into this DB and another process will identify it as not being processed and send the record to the SaaS product. This is the query that I am looking to modify. I was able to do a !list.Contains(c.swHDCaseId) initially, but this cannot handle more than 2100 items. Is there a way to add a join to the other context? var query = (from c in contextA.Cases where monitoredInboxList.Contains(c.INBOXES.inboxName) select new { //setup fields here... });

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  • Which of these queries is preferable?

    - by bread
    I've written the same query as a subquery and a self-join. Is there any obvious argument for one over the other here? SUBQUERY: SELECT prod_id, prod_name FROM products WHERE vend_id = (SELECT vend_id FROM products WHERE prod_id = ‘DTNTR’); SELF-JOIN: SELECT p1.prod_id, p1.prod_name FROM products p1, products p2 WHERE p1.vend_id = p2.vend_id AND p2.prod_id = ‘DTNTR’;

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