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  • MySQL- complex data query in a single statement

    - by yoda
    Hi, Consider the following structure : Ignore the table user_token. Now, imagine that you need to get all the roles related to an user, wich may be through it's related groups or directly related to him. In case the same role appears related to a group and the user directly, the role related to the user will prevail over the role given by the group. Is there any chance this could be done in a single query? Cheers!

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  • Removing certain characters in all rows that match a regex?

    - by user001
    I'd like to change {foo, {bar}, foobar} to {foo, bar, foobar} in all rows that match '{.*{'. I.e. remove all curly braces { and } except the outer most pair. So doing mysql -h $H -u $U -p$P $DB -B -e "SELECT id FROM t WHERE col REGEXP '{.*{'" > bad.txt selects all the rows that will need this substitution. How do I make this substitution very quickly? EDIT: Could I do it by update table set column = REPLACE(column,'{',''); Then restore the out most pair update table set column = REPLACE(column,'^','{'); update table set column = REPLACE(column,'$','}');

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  • Can't create a MySQL query that generates 4 rows for each row in the table it references.

    - by UkraineTrain
    I need to create a MySQL query that generates 4 rows for each row in the table it references. I need some of the information in those rows to repeat and some to be different. In the table each row stands for one day. I need to break the day up in 6 hour increments, hence the four rows for each entry. I need to create one column which for each day will have '12AM', '6AM', '12PM', and '6PM' values and another column will have the corresponding numeric values calculated for those entries. Thanks a lot in advance and I will really appreciate any help on this.

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  • how to debug a query that has valid syntax, executes, but returns no results?

    - by Ty W
    So I'm writing a fairly involved query with a half dozen joins, a dependent subquery for [greatest-n-per-group] purposes, grouping, etc. It is syntactically valid, but I've clearly made at least one mistake because it returns nothing. In the past I've debugged valid queries that return nothing by removing joins, executing subqueries on their own, removing WHERE conditions, and removing grouping to see what I would get but so far this one has me stumped. Are there better tools or techniques to use for this sort of thing? This particular query is for MySQL if it matters for any platform-specific tools.

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  • Use database dynamically

    - by Redi
    This execution it is giving me an error! Any hints of what am I missing? declare @dbname varchar(500) set @dbname='master' Exec (' Use ' + @dbname + ' go create PROCEDURE [dbo].[krijo_database] @dbname nvarchar(2000), @Direktoria varchar(4000) AS BEGIN declare @stringu nvarchar(100) set @stringu = ''CREATE DATABASE '' + @dbname exec (@stringu) End ')

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  • fastest way to copy a table in mysql

    - by Anon
    which one is the fastest way to completely copy a table on mysql ? CREATE TABLE copy LIKE original; INSERT INTO copy SELECT * FROM original; or CREATE TABLE copy SELECT * FROM original; ALTER TABLE copy ADD PRIMARY KEY (id); or theres another way ? PS. can't use command-line tools like mysqldump, must be on-the-fly.

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  • making a combined sum of two columns

    - by bsandrabr
    I have a table (apples) containing: cid date_am date_pm ---------------------- 1 1 1 2 2 1 3 1 3 1 1 2 I asked a question earlier (badly) about how I would rank the customers in order of the number of ones(1) they had. The solution was (based on one column): SELECT cid, sum( date_pm ) AS No_of_ones FROM apples WHERE date_am =1 GROUP BY cid ORDER BY no_of_ones DESC This works great for one column but how would I do the same for the sum of the two columns. ie. SELECT cid, sum( date_pm ) AS No_of_ones FROM apples WHERE date_am =1 add to SELECT cid, sum( date_am ) AS No_of_ones FROM apples WHERE date_pm =1 GROUP by cid ORDER by no_of_ones(added) hope I've managed to make that clear enough for you to help -thanks

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  • Can I have a CASE statement within a WHILE loop?

    - by John
    This is what I'm doing: while (@counter < 3 and @newBalance >0) begin CASE when @counter = 1 then ( @monFee1 = @monthlyFee, @newBalance = @newBalance-@fee) when @counter = 2 then ( @monFee2 = @monthlyFee, @newBalance = @newBalance-@fee) END @counter = @counter +1 end I get this error: Incorrect syntax near the keyword 'CASE'. No idea why. Please help!

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  • array insert in db

    - by gloris
    Hi, How best to put the array (100 or more length) in the database (MySQL)? I do not want multiple access to the database because it is so loaded. So my solution is as follows: string insert = "INSERT INTO programs (name, id) VALUES "; for(int i = 0; i < name.Length; i++) { if (i != 0) { insert = insert + ",("; } else { insert = insert + "("; } insert = insert + "'" + name[i] + "','" + id[i] + "'"; insert = insert + ")"; } //INSERT INTO programs (name, id) VALUES ('Peter','32'),('Rikko','343') .... But maybe is a faster version? Thanks

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  • How can I tell when a MySQL table was last updated?

    - by RaGE
    In the footer of my page, I would like to add something like "last updated the xx/xx/200x"; with this date being the last time a certain mySQL table has been updated. What is the best way to do that ? Is there a function to retrieve the date ? Should I make an access to the database everytime my footer is displayed ?

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  • Relation to multiple tables of different types for rating?

    - by Tronic
    i have a table structure like this Products Team Images and want to implement a rating/commenting-feature, where users can rate each entry of all tables. what's the best way to make a single rating table? e.g. a user votes a a product and a team entry, and it should be possible to get alle these entries from a single table. what kind of table-structure is best for this purpose? i hope, my questions is clear enough :/ thanks in advance!

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  • Using NULL in MySQL

    - by JPro
    The data in my dabatase comes from an external source and where ever there is no data passed, I keep NULL in those places. Can anyone tell me if there are any implications in using NULL to represent empty value? Should I follow some other convention like 'data_not_available'? or something like that? Can anyone suggest?

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  • reset all logged in users after they shutdown their consoled

    - by gin
    i have list of student who have Nintendo DSs, and they should log in my website to solve some sheets (by using DS Opera browser), when they logged in , (status filed at my DB will change from 0 to 1),also the status change to 0 if they log out, what i need is when the student didn't log out and Shut down their DS's , the status should be 0,, i don't have an idea to it, any suggestion would be helpful for me .. FYI ,DS opera browser limitation here

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  • Why is Postgres doing a Hash in this query?

    - by Claudiu
    I have two tables: A and P. I want to get information out of all rows in A whose id is in a temporary table I created, tmp_ids. However, there is additional information about A in the P table, foo, and I want to get this info as well. I have the following query: SELECT A.H_id AS hid, A.id AS aid, P.foo, A.pos, A.size FROM tmp_ids, P, A WHERE tmp_ids.id = A.H_id AND P.id = A.P_id I noticed it going slowly, and when I asked Postgres to explain, I noticed that it combines tmp_ids with an index on A I created for H_id with a nested loop. However, it hashes all of P before doing a Hash join with the result of the first merge. P is quite large and I think this is what's taking all the time. Why would it create a hash there? P.id is P's primary key, and A.P_id has an index of its own.

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  • How to add user customized data to database?

    - by CSharperWithJava
    I am trying to design a sqlite database that will store notes. Each of these notes will have common fields like title, due date, details, priority, and completed. In addition though, I would like to add data for more specialized notes like price for shopping list items and author/publisher data for books. I also want to have a few general purpose fields that users can fill with whatever text data they want. How can I design my database table in this case? I could just have a field for each piece of data for every note, but that would waste a lot of fields and I'd like to have other options and suggestions.

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  • Linq order by aggregate in the select { }

    - by Joe Pitz
    Here is one I am working on: var fStep = from insp in sq.Inspections where insp.TestTimeStamp > dStartTime && insp.TestTimeStamp < dEndTime && insp.Model == "EP" && insp.TestResults != "P" group insp by new { insp.TestResults, insp.FailStep } into grp select new { FailedCount = (grp.Key.TestResults == "F" ? grp.Count() : 0), CancelCount = (grp.Key.TestResults == "C" ? grp.Count() : 0), grp.Key.TestResults, grp.Key.FailStep, PercentFailed = Convert.ToDecimal(1.0 * grp.Count() /tcount*100) } ; I would like to orderby one or more of the fields in the select projection.

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  • What is the reason not to use select * ?

    - by Chris Lively
    I've seen a number of people claim that you should specifically name each column you want in your select query. Assuming I'm going to use all of the columns anyway, why would I not use SELECT *? Even considering the question from 9/24, I don't think this is an exact duplicate as I'm approaching the issue from a slightly different perspective. One of our principles is to not optimize before it's time. With that in mind, it seems like using SELECT * should be the preferred method until it is proven to be a resource issue or the schema is pretty much set in stone. Which, as we know, won't occur until development is completely done. That said, is there an overriding issue to not use SELECT *?

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  • MS access refusing to combine two tables?

    - by Mahmoud
    hey everyone i have an access 2007 database where i have 2 tables one is exp_cash and exp_cheque each are link to exp_cat, where exp_cat contains categories list where exp_cash contains id,cat_id,exp_date,exp_amount,exp_note same thing in exp_cheque where when i came to combine them nothing in result unless i remove the cat_name from my query i used a simple query which is SELECT DISTINCT exp_cat.cat_name, exp_cash.exp_amount, exp_cheque.exp_amount FROM (exp_cat INNER JOIN exp_cash ON exp_cat.ID = exp_cash.exp_cat_id) INNER JOIN exp_cheque ON exp_cat.ID = exp_cheque.exp_cat_id;

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  • Losing scope for DataContex using LINQToSQL intermediately

    - by greektreat
    I am having a weird Situation with my DataConext. All My code is in C# I have a DLL project for my data access layer and business Layer which and Winforms project for my UI layer. My Data access Layer's Namespace is xxx.Data this is where have my xxx.dbml I also have xxx.Data.BusinessObjects name space of course for my business object in that project In my UI Layer I have these namespaces xxxApp(for Forms), xxxApp.Controls (For Controls) I have lost scope of the DataContext, it was accessible now when I do a Rebuild Solution I sometimes get compile errors saying for example: Error 34 'xxx.Data.xxxDataContext' does not contain a definition for 'SubmitChanges' and no extension method 'SubmitChanges' accepting a first argument of type 'xxx.Data.xxxDataContext' could be found (are you missing a using directive or an assembly reference?) Also intelisense doesn't recognize the methods and table classes from my xxxDataContext anymore I can access all object fine when I am in the DLL project but now in the Winforms project this is very strange. If anyone can help me out I would be extremely grateful!

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  • PHP Security checklist (injection, sessions etc)

    - by NoviceCoding
    So what kind of things should a person using PHP and MySql be focused on to maximize security. Things I have done: -mysql_real_escape_string all inputs -validate all inputs after escaping em -Placed random alpha numerics before my table names -50character salt + Ripemd passwords Heres where I think I am slacking: -I know know nothing about sessions and securing them. How unsafe/safe is it if all you are doing is: session_start(); $_SESSION['login']= $login; and checking it with: session_start(); if(isset($_SESSION['login'])){ -I heard something about other forms of injection like cross site injection and what not... -And probably many other things I dont know about. Is there a "checklist"/Quicktut on making php secure? I dont even know what I should be worried about.I kinda regret now not building off cakephp since I am not a pro.

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