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  • How can I find columns which have non-null values?

    - by aartist
    I have many columns in oracle database and some new are added with values. I like to find out which columns have values other than 0 or null. So I am looking for column names for which some sort of useful values exists at least in one row. How do I do this? Update: This sounds very close. How do I modify this to suit my needs? select column_name, nullable, num_distinct, num_nulls from all_tab_columns where table_name = 'SOME_TABLE'

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  • Left outer joins that don't return all the rows from T1

    - by Summer
    Left outer joins should return at least one row from the T1 table if it matches the conditions. But what if the left outer join performs a join successfully, then finds that another criterion is not satisfied? Is there a way to get the query to return a row with T1 values and T2 values set to NULL? Here's the specific query, in which I'm trying to return a list of candidates, and the user's support for those candidates IF such support exists. SELECT c.id, c.name, s.support FROM candidates c LEFT JOIN support s on s.candidate_id = c.id WHERE c.office_id = 5059 AND c.election_id = 92 AND (s.user_id = 2 OR s.user_id IS NULL) --This line seems like the problem ORDER BY c.last_name, c.name The query joins the candidates and support table, but finds that it's a different user who supported this candidate (user_id=3, say). Then the candidate disappears entirely from the result set.

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  • XML Import how would you do it?

    - by Rico
    XML is used as one of our main integration points. it comes over by many clients at a time but too many clients importing at the same time can slow down our database to a crawl. Someone has to have solved a problem like this. I am basically using VB to parse through the data and import what i want and don't want. Is there a better way?

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  • Using LEFT JOIN to only selection one joined row

    - by Alex
    I'm trying to LEFT JOIN two tables, to get a list of all rows from TABLE_1 and ONE related row from TABLE_2. I have tried LEFT JOIN and GROUP BY c_id, however I wan't the related row from TABLE_2 to be sorted by isHeadOffice DESC. Here are some sample tables TABLE 1 c_id Name ---------------- 1 USA 2 Canada 3 England 4 France 5 Spain TABLE2 o_id c_id Office isHeadOffice ------------------------------------------------ 1 1 New York 1 2 1 Washington 0 3 1 Boston 0 4 2 Toronto 0 5 3 London 0 6 3 Manchester 1 7 4 Paris 1 8 4 Lyon 0 So what I am trying to get from this would be something like: RESULTS c_id Name Office ---------------------------- 1 USA New York 2 Canada Toronto 3 England Manchester 4 France Paris 5 Spain NULL I'm using PHP & MySQL. Any ideas?

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  • is it possible to combine will_paginate with find_by_sql?

    - by Tam
    In my rails application I want to use will_paginate plugin to paginate on my query. Is that possible? I tried doing something like this but it didn't work: @users = User.find_by_sql(" SELECT u.id, u.first_name, u.last_name, CASE WHEN r.user_accepted =1 AND (r.friend_accepted =0 || r.friend_accepted IS NULL) .........").paginate( :page => @page, :per_page => @per_page, :conditions => conditions_hash, :order => 'first_name ASC') If not, can you recommend a way around this or a way that might work as I don't want to write my own pagination.

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  • Question on different ways to link tables

    - by dotnetdev
    What is the difference between linking two tables and then the PK is an FK in the other table, but the FK has not got the primary key option (so it does not have the gold key), and having the PK in one table as a PK in another table? Am I right to think that the second option is for a many-to-many relationship? Thanks

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  • Speeding up a group by date query on a big table in postgres

    - by zaius
    I've got a table with around 20 million rows. For arguments sake, lets say there are two columns in the table - an id and a timestamp. I'm trying to get a count of the number of items per day. Here's what I have at the moment. SELECT DATE(timestamp) AS day, COUNT(*) FROM actions WHERE DATE(timestamp) >= '20100101' AND DATE(timestamp) < '20110101' GROUP BY day; Without any indices, this takes about a 30s to run on my machine. Here's the explain analyze output: GroupAggregate (cost=675462.78..676813.42 rows=46532 width=8) (actual time=24467.404..32417.643 rows=346 loops=1) -> Sort (cost=675462.78..675680.34 rows=87021 width=8) (actual time=24466.730..29071.438 rows=17321121 loops=1) Sort Key: (date("timestamp")) Sort Method: external merge Disk: 372496kB -> Seq Scan on actions (cost=0.00..667133.11 rows=87021 width=8) (actual time=1.981..12368.186 rows=17321121 loops=1) Filter: ((date("timestamp") >= '2010-01-01'::date) AND (date("timestamp") < '2011-01-01'::date)) Total runtime: 32447.762 ms Since I'm seeing a sequential scan, I tried to index on the date aggregate CREATE INDEX ON actions (DATE(timestamp)); Which cuts the speed by about 50%. HashAggregate (cost=796710.64..796716.19 rows=370 width=8) (actual time=17038.503..17038.590 rows=346 loops=1) -> Seq Scan on actions (cost=0.00..710202.27 rows=17301674 width=8) (actual time=1.745..12080.877 rows=17321121 loops=1) Filter: ((date("timestamp") >= '2010-01-01'::date) AND (date("timestamp") < '2011-01-01'::date)) Total runtime: 17038.663 ms I'm new to this whole query-optimization business, and I have no idea what to do next. Any clues how I could get this query running faster?

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  • update record only works when there is no auto_increment

    - by every_answer_gets_a_point
    i am accessing a mysql table through an odbc connection in excel here is how i am updating the table: With rs .AddNew ' create a new record ' add values to each field in the record .Fields("datapath") = dpath .Fields("analysistime") = atime .Fields("reporttime") = rtime .Fields("lastcalib") = lcalib .Fields("analystname") = aname .Fields("reportname") = rname .Fields("batchstate") = "bstate" .Fields("instrument") = "NA" .Update ' stores the new record End With when the schema of the table is this, updating it works: create table batchinfo(datapath text,analysistime text,reporttime text,lastcalib text,analystname text, reportname text, batchstate text, instrument text); but when i have auto_increment in there it does not work: CREATE TABLE batchinfo ( rowid int(11) NOT NULL AUTO_INCREMENT, datapath text, analysistime text, reporttime text, lastcalib text, analystname text, reportname text, batchstate text, instrument text, PRIMARY KEY (rowid) ) ENGINE=InnoDB AUTO_INCREMENT=67 DEFAULT CHARSET=latin1 has anyone experienced a problem like this where updating does not work when there is an auto_increment field involved? connection string: Private Sub ConnectDB() Set oConn = New ADODB.Connection oConn.Open "DRIVER={MySQL ODBC 5.1 Driver};" & _ "SERVER=localhost;" & _ "DATABASE=employees;" & _ "USER=root;" & _ "PASSWORD=pas;" & _ "Option=3" End Sub also here's the rs.open: rs.Open "batchinfo", oConn, adOpenKeyset, adLockOptimistic, adCmdTable

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  • MySQL - accessing a table sum and compare to another table?

    - by assignment_operator
    This is for a homework assignment. I just plain don't understand how to do it. The instructions for this particular question is: List the branch name for all branches that have at least one book that has at least 4 copies on hand. Where the tables in question are: Branch: BranchName | BranchId Henry Downtown | 1 16 Riverview | 2 Henry On The Hill | 3 Inventory: BookId | BranchId | OnHand 1 | 1 | 2 2 | 3 | 4 3 | 1 | 8 4 | 3 | 1 5 | 1 | 2 6 | 2 | 3 From what I understand, I can get the number of OnHand per branch name with: SELECT BranchName, SUM(OnHand) FROM Branch B, Inventory I WHERE B.BranchId = I.BranchId GROUP BY BranchName; but I don't get how I'd do the comparison between the sum of OnHand per branch and 4. Any help would be appreciated, guys!

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  • Get top 'n' records by report_id

    - by Skudd
    I have a simple view in my MSSQL database. It consists of the following fields: report_id INT ym VARCHAR -- YYYY-MM keyword VARCHAR(MAX) visits INT I can easily get the top 10 keyword hits with the following query: SELECT TOP 10 * FROM top_keywords WHERE ym BETWEEN '2010-05' AND '2010-05' ORDER BY visits DESC Now where it gets tricky is where I have to get the top 10 records for each report_id in the given date range (ym BETWEEN @start_date AND @end_date). How would I go about getting the top 10 for each report_id? I've stumbled across suggestions involving the use of ROW_NUMBER() and RANK(), but have been vastly unsuccessful in their implementation.

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  • How to hide folder in SSRS Report Builder?

    - by tnafoo
    When I click File - Open on Report Builder, I can see a list of folders under Report Server Home root folder. But I don't want end-user to see any of the folders under root unless I grant them access. I tried hiding and removing permission on the folders but they are still visible in the root folder.

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  • Coalesce and Case-When with To_Date not working as expected (Postgres bug?)

    - by ADTC
    I'm using Postgres 9.1. The following query does not work as expected. Coalesce should return the first non-null value. However, this query returns null (1?) instead of the date (2). select COALESCE( TO_DATE('','yyyymmdd'), --(1) TO_DATE('20130201','yyyymmdd') --(2) ); --(1) this evaluates independently to null --(2) this evaluates independently to the date, and therefore is the first non-null value What am I doing wrong? Any workaround? Edit: This may have nothing to do with Coalesce at all. I tried some experiments with Case When constructs; it turns out, Postgres has this big ugly bug where it treats TO_DATE('','yyyymmdd') as not null, even though selecting it returns null.

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  • Mutiple FK columns all pointing to the same parent table - a good idea?

    - by Randy Minder
    For those of you who live and breath database design, have you ever found compelling reasons to have multiple FK's in a table that all point to the same parent table? We recently had to deal with a situation where we had a table that contained six columns which were all FK columns to the same parent table. We're debating whether this indicates a poor design on our part or whether this is more common than we think. Thanks very much.

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  • SQL Server Reporting Services using of pictures with dynamic links

    - by YvesR
    I have setup a SSRS 2008 and building reports. So far so good. Now there is a picture control in SSRS where you can set the picture as external link reference. There you can choose to use a link. When I use a weblink (http://anyurl/download_picture.aspx?id=123) it dont' work for me. Calling the url in the web browser (all tested IE, Safari, Chrome, FF) the pictures is delivered, Header is ok, content type, too. Does it work in general in SSRS ? Or do I have to copy the picture to a temp folder and link the url like http://anyurl/mypicture.jpg.

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  • Where to start with the development of first database driven Web App (long question)?

    - by Ryan
    Hi all, I've decided to develop a database driven web app, but I'm not sure where to start. The end goal of the project is three-fold: 1) to learn new technologies and practices, 2) deliver an unsolicited demo to management that would show how information that the company stores as office documents spread across a cumbersome network folder structure can be consolidated and made easier to access and maintain and 3) show my co-workers how Test Drive Development and prototyping via class diagrams can be very useful and reduces future maintenance headaches. I think this ends up being a basic CMS to which I have generated a set of features, see below. 1) Create a database to store the site structure (organized as a tree with a 'project group'-project structure). 2) Pull the site structure from the database and display as a tree using basic front end technologies. 3) Add administrator privileges/tools for modifying the site structure. 4) Auto create required sub pages* when an admin adds a new project. 4.1) There will be several sub pages under each project and the content for each sub page is different. 5) add user privileges for assigning read and write privileges to sub pages. What I would like to do is use Test Driven Development and class diagramming as part of my process for developing this project. My problem; I'm not sure where to start. I have read on Unit Testing and UML, but never used them in practice. Also, having never worked with databases before, how to I incorporate these items into the models and test units? Thank you all in advance for your expertise.

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  • How to login users that are stored within a Wordpress account

    - by user3716795
    I am developing an iOS app that is password protected and all the users are stored in a wordpress account that, of course, is password protected as well. Does anybody know the format that wordpress uses to store login information for these accounts, I would assume that it is a MySQL that sends a json? I have only been able to find the database code for the initial admin page but nothing that shows the way these accounts (815 to be exact) would be stored within the site.

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  • How to handle un-assigned records

    - by Mico
    I have this PHP page where the user can select and un-select items. The interface looks like this: Now I'm using these code, when the user hit the save changes button: foreach( $value as $al_id ){ //al_id is actually location id //check if a record exists //if location were assigned and leave it as is $assigned_count = $this->AssignedLoc->checkIfAssigned( $tab_user_id, $al_id ); if( $assigned_count == 0 ){ //else if not, insert this new record $this->insertAssigned( $tab_user_id, $company_id, $al_id ); } } Now my question is, how do I delete the un assigned locations? For example in the screenshot above, there are 4 assigned locations, if I'm gonna remove (or unassign) "Mercury Morong" and "GP Hagonoy" from the assigned locations, only two must remain. What are the possible solutions using PHP? Thanks for any help!

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  • How can I do a multi level parent-child sort using Linq?

    - by Tenacious T
    How can I do a multi-level parent-child sort using Linq if I have a table structure like the one below: [Table: Sections] Id Seq Name ParentSectionId 1 1 TOP NULL 2 1 AAAA 1 3 2 SSSS 1 4 3 DDDD 1 5 1 SectionA1 2 6 2 SectionA2 2 7 1 SectionS1 3 8 3 ASummary 2 Expected sort result: TOP AAAA SectionA1 SectionA2 ASummary SSSS SectionS1 DDDD

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  • Worpress WorkFlow Modfications

    - by blgnklc
    Hi All WordPress Lovers, I would like to ask a help about Zensor which is a plugin that you publish a post then a moderator approves the post to be published on the wordpress blog site. When a post is awating for approval, each awaiting post is appearing "waiting moderation". But, I dont want any link appears before moderator approval. Actually I found the joing sentence below; 1- Must be added to the end of JOIN part of any query: LEFT JOIN wp_zensor ON ID = wp_zensor.post_id 2- Must be added to the end of WHERE condition : AND wp_zensor.moderation_status = 'approved' Could you please show me; where should I add these modification on the category link presentation below: <h2>Politics</h2> <?php $recent = new WP_Query("cat=31&showposts=1"); while($recent->have_posts()) : $recent->the_post();?> <b><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></b> <?php the_content_limit(140, "devami &raquo;"); ?> <div class="hppostmeta"> <p><?php the_time('j F Y, H:i'); ?> | <?php the_author_posts_link(); ?></p> </div> <?php endwhile; ?> Or any general solutions will be welcomed. Thanks. BK

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  • View Lambdas in Visual Studio Debugger

    - by Vaccano
    I have the a simple LinqToSQL statement that is not working. Something Like this: List<MyClass> myList = _ctx.DBList .Where(x => x.AGuidID == paramID) .Where(x => x.BBoolVal == false) .ToList(); I look at _ctx.DBList in the debugger and the second item fits both parameters. Is there a way I can dig into this more to see what is going wrong?

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