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  • should this database table be normalized?

    - by oo
    i have taken over a database that stores fitness information and we were having a debate about a certain table and whether it should stay as one table or get broken up into three tables. Today, there is one table called: workouts that has the following fields id, exercise_id, reps, weight, date, person_id So if i did 2 sets of 3 different exercises on one day, i would have 6 records in that table for that day. for example: id, exercise_id, reps, weight, date, person_id 1, 1, 10, 100, 1/1/2010, 10 2, 1, 10, 100, 1/1/2010, 10 3, 1, 10, 100, 1/1/2010, 10 4, 2, 10, 100, 1/1/2010, 10 5, 2, 10, 100, 1/1/2010, 10 6, 2, 10, 100, 1/1/2010, 10 So the question is, given that there is some redundant data (date, personid, exercise_id) in multiple records, should this be normalized to three tables WorkoutSummary: - id - date - person_id WorkoutExercise: - id - workout_id (foreign key into WorkoutSummary) - exercise_id WorkoutSets: - id - workout_exercise_id (foreign key into WorkoutExercise) - reps - weight I would guess the downside is that the queries would be slower after this refactoring as now we would need to join 3 tables to do the same query that had no joins before. The benefit of the refactoring allows up in the future to add new fields at the workout summary level or the exercise level with out adding in more duplication. any feedback on this debate?

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  • Analyzing data from same tables in diferent db instances.

    - by Oscar Reyes
    Short version: How can I map two columns from table A and B if they both have a common identifier which in turn may have two values in column C Lets say: A --- 1 , 2 B --- ? , 3 C ----- 45, 2 45, 3 Using table C I know that id 2 and 3 belong to the same item ( 45 ) and thus "?" in table B should be 1. What query could do something like that? EDIT Long version ommited. It was really boring/confusing EDIT I'm posting some output here. From this query: select distinct( rolein) , activityin from taskperformance@dm_prod where activityin in ( select activityin from activities@dm_prod where activityid in ( select activityid from activities@dm_prod where activityin in ( select distinct( activityin ) from taskperformance where rolein = 0 ) ) ) I have the following parts: select distinct( activityin ) from taskperformance where rolein = 0 Output: http://question1337216.pastebin.com/f5039557 select activityin from activities@dm_prod where activityid in ( select activityid from activities@dm_prod where activityin in ( select distinct( activityin ) from taskperformance where rolein = 0 ) ) Output: http://question1337216.pastebin.com/f6cef9393 And finally: select distinct( rolein) , activityin from taskperformance@dm_prod where activityin in ( select activityin from activities@dm_prod where activityid in ( select activityid from activities@dm_prod where activityin in ( select distinct( activityin ) from taskperformance where rolein = 0 ) ) ) Output: http://question1337216.pastebin.com/f346057bd Take for instace activityin 335 from first query ( from taskperformance B) . It is present in actvities from A. But is not in taskperformace in A ( but a the related activities: 92, 208, 335, 595 ) Are present in the result. The corresponding role in is: 1

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  • LLBLGEN: Linq to LLBGEN don't work

    - by StreamT
    I want to make custom select from the database table using Linq. We use LLBGEN as ORM solution. I can't do LINQ query to Entities Collection Class unless I call GetMulti(null) method of it. Is it possible to do LINQ query to LLBGEN without extracting all table first? BatchCollection batches = new BatchCollection(); BatchEntity batch = batches.AsQueryable() .Where(i => i.RegisterID == 3) .FirstOrDefault(); // Exception: Sequence don't contains any elements batches = new BatchCollection(); batches.GetMulti(null); // I don't want to extract the whole table. BatchEntity batch = batches.AsQueryable() .Where(i => i.RegisterID == 3) .FirstOrDefault(); //Works fine

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  • Passing sql results to views hard-codes views to database column names

    - by Galen
    I just realized that i may not be following best practices in regards to the MVC pattern. My issue is that my views "know" information about my database Here's my situation in psuedo code... My controller invokes a method from my model and passes it directly to the view view.records = tableGateway.getRecords() view.display() in my view each records as record print record.name print record.address ... In my view i have record.name and record.address, info that's hard-coded to my database. Is this bad? What other ways around it are there other than iterating over everything in the controller and basically rewriting the records collection. And that just seems silly. Thanks

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  • Linq Projection Question

    - by Micah
    I'm trying to do the following: from c in db.GetAllContactsQuery() select new { ID= c.ID, LastName = c.LastName, FirstName = c.FirstName, Email = c.Email, City =c.City+" "+c.State } The issue i'm running into is that if c.City or c.State are null, the City property returns null. How can I put a function right beside that City= declaration?

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  • How do I select the max value from multiple tables in one column

    - by Derick
    I would like to get the last date of records modified. Here is a sample simple SELECT: SELECT t01.name, t01.last_upd date1, t02.last_upd date2, t03.last_upd date3, 'maxof123' maxdate FROM s_org_ext t01, s_org_ext_x t02, s_addr_org t03 WHERE t02.par_row_id(+)= t01.row_id and t03.row_id(+)= t01.pr_addr_id and t01.int_org_flg = 'n'; How can I get column maxdate to display the max of the three dates? Note: no UNION or sub SELECT statements ;)

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  • How can I write query to output this format in SQLite?

    - by GivenPie
    I would like to output in this format: e.EE_id e.FNAME e.LNAME SUPer_id s.FNAME s.LNAME --- --------- -------------- --- ------------- ------------------- 1 Ziqiao Li 2 Charlie Li 1 Ziqiao Li 3 George Pee 2 Charlie Li 4 Jason Dee 2 Charlie Li 5 Petey Wee 2 Charlie Li From this table created : I need to display the Primary key and foreign key in the same results while displaying the foreign key name values for the primary key names. Create table Employees( ee_id integer, fname varchar(20), lname varchar(20), super_id integer, Constraint emp_Pk Primary Key (ee_id), Constraint emp_Fk Foreign Key (super_id) references employees (ee_id) ); INSERT INTO Employees VALUES(1,'Charlie','Li',null); INSERT INTO Employees VALUES(2,'Ziqiao','Lee',1); INSERT INTO Employees VALUES(3,'George','Pee',2); INSERT INTO Employees VALUES(4,'Jason','Dee',2); INSERT INTO Employees VALUES(5,'Petey','Wee',2); Select ee_id, fname, lname, super_id from employees; ee_id fname lname super_id ---------- ---------- ---------- ---------- 1 Charlie Li 2 Ziqiao Lee 1 3 George Pee 2 4 Jason Dee 2 5 Petey Wee 2 Do I need to create a view?

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  • Optimize mysql table ?

    - by fabien-barbier
    Here is my actual table schema (I'm using Mysql) : Table experiment : code(int) sample_1_id sample_2_id ... until ... sample_12_id rna_1_id rna_2_id ... until ... rna_12_id experiment_start How can I optimize both part : sample_n_id and rna_n_id (all are bigint(20) and allow null=true) ? About values : we can have : ex : sample_1_id = 2 , Sample_2_id = 5 , ... Note : values can be updated. Ideas ? Thanks.

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  • SSIS DTSX File Repair Tool

    - by Eric Ness
    I'm working with an SSIS 2005 file that crashes Visual Studio 2005 on my workstation. This happens when I open the data flow diagram and Visual Studio attempts to validate the package. I can open it successfully on another computer though. The package itself is fairly simple and only has two control flow tasks and maybe ten tasks in the data flow. I'm wondering if there is a tool that goes through the XML in the dtsx file and repairs any issues or if this is even necessary. The dtsx file is about 171 kB and it seems like there's a lot in it considering what a simple package it is.

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  • How to provide a date variable an interval that consists of an integer variable in Postgresql

    - by Lucius Rutilius Lupus
    I am trying to extract an amount of years from a specific date for this the correct syntax is <date> - interval '5 years'; But I dont want to extract a specific amount of years but a variable, which user will provide as a parameter. I have tried the following the variable name is years : date+interval '% years',years; I am getting an error and it doesn't let me do it that way. What would be the right way to do it.

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  • get column names from a table where one of the column name is a key word.

    - by syedsaleemss
    Im using c# .net windows form application. I have created a database which has many tables. In one of the tables I have entered data. In this table I have 4 columns named key, name,age,value. Here the name "key" of the first column is a key word. Now I am trying to get these column names into a combo box. I am unable to get the name "key". It works for "key" when I use this code: private void comboseccolumn_SelectedIndexChanged(object sender, EventArgs e) { string dbname = combodatabase.SelectedItem.ToString(); string path = @"Data Source=" + textBox1.Text + ";Initial Catalog=" + dbname + ";Integrated Security=SSPI"; //string path=@"Data Source=SYED-PC\SQLEXPRESS;Initial Catalog=resources;Integrated Security=SSPI"; SqlConnection con = new SqlConnection(path); string tablename = comboBox2.SelectedItem.ToString(); //string query= "Select * from" +tablename+; //SqlDataAdapter adp = new SqlDataAdapter(" Select [Key] ,value from " + tablename, con); SqlDataAdapter adp = new SqlDataAdapter(" Select [" + combofirstcolumn.SelectedItem.ToString() + "]," + comboseccolumn.SelectedItem.ToString() + "\t from " + tablename, con); DataTable dt = new DataTable(); adp.Fill(dt); dataGridView1.DataSource = dt; } This is beacuse I am using "[" in the select query. But it wont work for non keys. Or if I remove the "[" it is not working for key . Please suggest me so that I can get both key as well as nonkey column names.

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  • what is the purpose of this mysql query ?

    - by Harbhag
    SELECT id, CONCAT(lastname,', ',firstname) AS fullname, lastname, firstname FROM " . TABLE_CONTACT . " WHERE CONCAT(firstname,' ', lastname) LIKE '%$goTo%' OR CONCAT(firstname,' ', middlename,' ', lastname) LIKE '%$goTo%' OR nickname LIKE '%$goTo%' ORDER BY fullname"; Can anyone please tell me what is purpose of above query ? I am new to mysql so unable to understand it. Thanks

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  • mysql error in php

    - by fusion
    i'm trying to run this php code which should display a quote from mysql, but can't figure out where is it going wrong. the result variable is null or empty. can someone help me out. thanks! <?php include 'config.php'; // 'text' is the name of your table that contains // the information you want to pull from $rowcount = mysql_query("select count(*) as rows from quotes"); // Gets the total number of items pulled from database. while ($row = mysql_fetch_assoc($rowcount)) { $max = $row["rows"]; //print_r ($max); } // Selects an item's index at random $rand = rand(1,$max)-1; print_r ($rand); $result = mysql_query("select * from quotes limit $rand, 1") or die ('Error: '.mysql_error()); if (!$result or mysql_num_rows($result)) { echo "Empty"; } else{ while ($row = mysql_fetch_array($result)) { $randomOutput = $row['cQuotes']; echo '<p>' . $randomOutput . '</p>'; } }

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  • what is called KEY

    - by Bharanikumar
    CREATE TABLE `ost_staff` ( `staff_id` int(11) unsigned NOT NULL auto_increment, `group_id` int(10) unsigned NOT NULL default '0', `dept_id` int(10) unsigned NOT NULL default '0', `username` varchar(32) collate latin1_german2_ci NOT NULL default '', `firstname` varchar(32) collate latin1_german2_ci default NULL, `lastname` varchar(32) collate latin1_german2_ci default NULL, `passwd` varchar(128) collate latin1_german2_ci default NULL, `email` varchar(128) collate latin1_german2_ci default NULL, `phone` varchar(24) collate latin1_german2_ci NOT NULL default '', `phone_ext` varchar(6) collate latin1_german2_ci default NULL, `mobile` varchar(24) collate latin1_german2_ci NOT NULL default '', `signature` varchar(255) collate latin1_german2_ci NOT NULL default '', `isactive` tinyint(1) NOT NULL default '1', `isadmin` tinyint(1) NOT NULL default '0', `isvisible` tinyint(1) unsigned NOT NULL default '1', `onvacation` tinyint(1) unsigned NOT NULL default '0', `daylight_saving` tinyint(1) unsigned NOT NULL default '0', `append_signature` tinyint(1) unsigned NOT NULL default '0', `change_passwd` tinyint(1) unsigned NOT NULL default '0', `timezone_offset` float(3,1) NOT NULL default '0.0', `max_page_size` int(11) NOT NULL default '0', `created` datetime NOT NULL default '0000-00-00 00:00:00', `lastlogin` datetime default NULL, `updated` datetime NOT NULL default '0000-00-00 00:00:00', PRIMARY KEY (`staff_id`), UNIQUE KEY `username` (`username`), KEY `dept_id` (`dept_id`), **KEY `issuperuser` (`isadmin`),** **KEY `group_id` (`group_id`,`staff_id`)** ) ENGINE=MyISAM AUTO_INCREMENT=35 DEFAULT CHARSET=latin1 COLLATE=latin1_german2_ci; Hi the above query is the osticket open source one, i know primary key , foreign key , unique but AM NOT SURE WHAT IS THIS KEY group_id (group_id,staff_id) Please tell me, this constraints name....

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  • How to evaluate query by DBMS?

    - by Kevinniceguy
    Sorry...I mean what question will be for this query? SELECT SUM(price) FROM Room r, Hotel h WHERE r.hotelNo = h.hotelNo and hotelName = 'Paris Hilton' and roomNo NOT IN (SELECT roomNo FROM Booking b, Hotel h WHERE (dateFrom <= CURRENT_DATE AND dateTo >= CURRENT_DATE) AND b.hotelNo = h.hotelNo AND hotelName = 'Paris Hilton');

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  • Problem counting item frequency on T-SQL

    - by Raúl Roa
    I'm trying to count the frequency of numbers from 1 to 100 on different fields of a table. Let's say I have the table "Results" with the following data: LottoId Winner Second Third --------- --------- --------- --------- 1 1 2 3 2 1 2 3 I'd like to be able to get the frequency per numbers. For that I'm using the following code: --Creating numbers temp table CREATE TABLE #Numbers( Number int) --Inserting the numbers into the temp table declare @counter int set @counter = 0 while @counter < 100 begin set @counter = @counter + 1 INSERT INTO #Numbers(Number) VALUES(@counter) end -- SELECT #Numbers.Number, Count(Results.Winner) as Winner,Count(Results.Second) as Second, Count(Results.Third) as Third FROM #Numbers LEFT JOIN Results ON #Numbers.Number = Results.Winner OR #Numbers.Number = Results.Second OR #Numbers.Number = Results.Third GROUP BY #Numbers.Number The problem is that the counts are repeating the same values for each number. In this particular case I'm getting the following result: Number Winner Second Third --------- --------- --------- --------- 1 2 2 2 2 2 2 2 3 2 2 2 ... When I should get this: Number Winner Second Third --------- --------- --------- --------- 1 2 0 0 2 0 2 0 3 0 0 2 ... What am I missing?

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  • Database design for invoices, invoice lines & revisions

    - by FreshCode
    I'm designing the 2nd major iteration of a relational database for a franchise's CRM (with lots of refactoring) and I need help on the best database design practices for storing job invoices and invoice lines with a strong audit trail of any changes made to each invoice. Current schema Invoices Table InvoiceId (int) // Primary key JobId (int) StatusId (tinyint) // Pending, Paid or Deleted UserId (int) // auditing user Reference (nvarchar(256)) // unique natural string key with invoice number Date (datetime) Comments (nvarchar(MAX)) InvoiceLines Table LineId (int) // Primary key InvoiceId (int) // related to Invoices above Quantity (decimal(9,4)) Title (nvarchar(512)) Comment (nvarchar(512)) UnitPrice (smallmoney) Revision schema InvoiceRevisions Table RevisionId (int) // Primary key InvoiceId (int) JobId (int) StatusId (tinyint) // Pending, Paid or Deleted UserId (int) // auditing user Reference (nvarchar(256)) // unique natural string key with invoice number Date (datetime) Total (smallmoney) Schema design considerations 1. Is it sensible to store an invoice's Paid or Pending status? All payments received for an invoice are stored in a Payments table (eg. Cash, Credit Card, Cheque, Bank Deposit). Is it meaningful to store a "Paid" status in the Invoices table if all the income related to a given job's invoices can be inferred from the Payments table? 2. How to keep track of invoice line item revisions? I can track revisions to an invoice by storing status changes along with the invoice total and the auditing user in an invoice revision table (see InvoiceRevisions above), but keeping track of an invoice line revision table feels hard to maintain. Thoughts? 3. Tax How should I incorporate sales tax (or 14% VAT in SA) when storing invoice data?

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  • Concatenation of fields in different rows

    - by spender
    I'm stuck on an aggregation problem that I can't get to the bottom of. I have some data which is best summarized as follows id |phraseId|seqNum|word ========================= 1 |1 |1 |hello 2 |1 |2 |world 3 |2 |1 |black 4 |2 |2 |and 5 |2 |3 |white I'd like a query that gives back the following data: phraseId|completePhrase ======================== 1 |hello world 2 |black and white Anyone?

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  • Should i really use integer primary IDs?

    - by arthurprs
    For example, i always generate an auto-increment field for the users table, but i also specifies an UNIQUE index on their usernames. There is situations that i first need to get the userId for a given username and then execute the desired query. Or use a JOIN in the desired query. It's 2 trips to the database or a JOIN vs. a varchar index The above is just an example There is a real performance benefit on INT over small VARCHAR indexes? Thanks in advance!

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  • I do I iterate the records in a database using LINQ when I have already built the LINQ DB code?

    - by Seth Spearman
    I asked on SO a few days ago what was the simplest quickest way to build a wrapper around a recently completed database. I took the advice and used sqlmetal to build linq classes around my database design. Now I am having two problems. One, I don't know LINQ. And, two, I have been shocked to realize how hard it is to learn. I have a book on LINQ (Linq In Action by Manning) and it has helped some but at the end of the day it is going to take me a couple of weeks to get traction and I need to make some progress on my project today. So, I am looking for some help getting started. Click HERE To see my simple database schema. Click HERE to see the vb class that was generated for the schema. My needs are simple. I have a console app. The main table is the SupplyModel table. Most of the other tables are child tables of the SupplyModel table. I want to iterate through each of Supply Model records. I want to grab the data for a supply model and then DoStuff with the data. And I also need to iterate through the child records, for each supply model, for example the NumberedInventories and DoStuff with that as well. I want to only iterate the SupplyModels that are have IDs that are in an array of strings containing the IDs. I need help doing this in VB rather than C# if possible. Thanks for your help. Seth

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  • ActiveRecord + CodeIgniter - Return single value from query, not in array form.

    - by txmail
    Say you construct an activerecord query that will always just return a single value, how do you just address that single value instead of getting an array in return? For instance I am using an ActiveRecord query to return the SUM of a single column, it will only return this one single SUM, instead of having to parse the array is there a way to assign the value as a function return equal to that value instead of getting an array?

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