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  • MySQL Select Statement - Two Tables, Sort One Table by Count of Other Table

    - by Robert Boka
    So I have built a voting system for a custom post system i wrote. I want to be able to sort by "most voted", "Most liked", etc. I have two tables. Entry: ID, Title, Post Vote: ID, EntryID, Result I want to be able to query the vote table for each entry and see how many vote's there are, and then sort the entry's by how many vote's each table had. I have messed around with joins, etc. and cannot seem to figure it out. Any suggestions?

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  • t-sql get variable value from string with variable name

    - by Markus
    Hi. Is there a way to convert '@my_variable' string into a value of @my_variable? I have a table which stores names of variables. I need to get the value of this variable. Something like this: DECLARE @second_variable AS NVARCHAR(20); DECLARE @first_variable AS NVARCHAR(20); SET @first_variable = '20'; SET @second_variable = SELECT '@first_variable'; --here I want that @second variable be assigned a value of "20".

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  • SQL trigger to delete rows from database

    - by wpearse
    I have an industrial system that logs alarms to a remotely hosted MySQL database. The industrial system inserts a new row whenever a property of the alarm changes (such as the time the alarm was activated, acknowledged or switched off) into a table named 'alarms'. I don't want multiple records for each alarm, so I have set up two database triggers. The first trigger mirrors each new record to a second table, creating/updating rows as required: CREATE TRIGGER `mirror_alarms` BEFORE INSERT ON `alarms` FOR EACH ROW INSERT INTO `alarm_display` (Tag,...,OffTime) VALUES (new.Tag,...,new.OffTime) ON DUPLICATE KEY UPDATE OnDate=new.OnDate,...,OffTime=new.OffTime The second trigger should execute after the first and (ideally) delete all rows from the alarms table. (I used the Tag property of the alarm because the Tag property never changes, although I suspect I could just use a 'DELETE FROM alarms WHERE 1' statement to the same effect). CREATE TRIGGER `remove_alarms` AFTER INSERT ON `alarms` FOR EACH ROW DELETE FROM alarms WHERE Tag=new.Tag My problem is that the second trigger doesn't appear to run, or if it does, the second trigger doesn't delete any rows from the database. So here's the question: why does my second trigger not do what I expect it to do?

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  • How to combine a list of choices to determine which select statement

    - by Larry
    I have a mysql db and am using php 5.2 What I am trying to do is offer a list of options for a person to select (only 1). The chosen option will cause a select, update, or delete statement to be ran. The results of the statement do not need to be shown, although, showing the old and then the new would be nice (no problems with that part tho'.). Pseudo-Code: Assign $choice = 0 Check the value of $choice // This way, if it = 100, we do a break Select a Choice:<br> 1. Adjust Status Value (+60) // $choice = 1<br> 2. Show all Ships <br> // $choice = 2 3. Show Ships in Port <br> // $choice = 3 ... 0. $choice="100" // if the value =100, quit this part Use either case (switch) or if/else statements to run the users choice1 If the choice is 1, then run the "Select" statement with the variable of $sql1 -- "SELECT .... If the choice is 2, then run the "Select" statement with the variable of $sql2 --- SELECT * FROM Ships If the choice is 3, then run the "Select" statement with the variable of $sql3 <br> .... If the choice is 0, then we are done. I figured the (3) statements would be assigned in php as: $sql1="...". $sql2="SELECT * FROM Ships" $sql3="SELECT * FROM Ships WHERE nPort="1" My idea was to use the switch statement, but got lost on it. :( I would like the options to be available over and over again, until a variable ($choice) is selected. In which case, this particular page is done and goes back to the "Main Menu"? The coding and display, if I use it, I can do. Just not sure how to write the way to select which one I want. It is possible that I would run all of the queries, and other times, only one, so that is why I would like the choice. An area I get confused in is the proper forms to use such as -- ' ' " " and ...?? Not sure the # of options I will end up with, but it will be more than 5 but less than 20 / page. So if I get the system down for 2-3 choices, I can replicate it for as many as I may need. And, as always, if a better way exists, I am willing to try it. Thanks again... Larry

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  • sp_help with wildcards

    - by serhio
    There is a command in SqlServer sp_help 'table_name' (table_name or other stuff) Is there a possibility to use it when you don't know the whole table name, with wildcards or something like this: sp_help admin_%

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  • Exceptions by DataContext

    - by Bas
    I've been doing some searching on the internet, but I can't seem to find the awnser. What exceptions can a DataContext throw? Or to be more specific, what exceptions does the DataContext.SubmitChanges() method throw?

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  • Use where condition with unjoined table

    - by Dragos D
    I have the following problem: I am trying to retreive a sum value based on one condition. Problem is that I can't join the conditional value since my tables aren't joined. Here is my syntax: SELECT SUM(value) FROM value v join day d on v.day_id = d.day_id join budget b on d.budget_id = b.budget_id join unit u on v.unit_id = u.unit_id where #output.class = (SELECT distinct s.class FROM sale s where s.id = #output.sale_id) AND u.unit_name in ('electronics') With this sybtax I get no error but neither values. Can you please tell me where I do wrong?

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  • How to retrieve the ordered list of best articles having a minimum number of votes by using HSQL ?

    - by fabien7474
    I have a Vote domain class from my grails application containing properties like article_id and note I want to HQL query the Vote domain class in order to retrieve the 5 best rated articles having at least 10 votes. I tried : SELECT v.article_id, avg(v.note), count(*) FROM vote v where count(*) >= 10 group by v.article_id order by avg(v.note) desc limit 5; But unfortunately the insertion of where count(*) >= 10 throws an error. How can I do that in a simple way? Thank you for your help.

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  • selecting a range of verses from a database

    - by Noam Smadja
    i have a database, with verses from the bible, with those fields: book (book number), chapter (chapter number), verse (verse number), text (the verse) example: 1 1 1 In the beginning God created the heaven and the earth. first 1 is for Genesis, second 1 is for chapter 1, third 1 is for verse 1 user gives me something like 1 1:1 - 1 1:4 which means he wants to show Genesis 1:1-4. what i want to do is something like SELECT book*100000+chapter*1000+verse AS index FROM bible WHERE index >= 1001001 AND index <=1001004 or WHERE book*100000+chapter*1000+verse >= 1001001 AND book*100000+chapter*1000+verse <= 1001004

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  • Left Join works with table but fails with query

    - by Frank Martin
    The following left join query in MS Access 2007 SELECT Table1.Field_A, Table1.Field_B, qry_Table2_Combined.Field_A, qry_Table2_Combined.Field_B, qry_Table2_Combined.Combined_Field FROM Table1 LEFT JOIN qry_Table2_Combined ON (Table1.Field_A = qry_Table2_Combined.Field_A) AND (Table1.Field_B = qry_Table2_Combined.Field_B); is expected by me to return this result: +--------+---------+---------+---------+----------------+ |Field_A | Field_B | Field_A | Field_B | Combined_Field | +--------+---------+---------+---------+----------------+ |1 | | | | | +--------+---------+---------+---------+----------------+ |1 | | | | | +--------+---------+---------+---------+----------------+ |2 |1 |2 |1 |John, Doe | +--------+---------+---------+---------+----------------+ |2 |2 | | | | +--------+---------+---------+---------+----------------+ [Table1] has 4 records, [qry_Table2_Combined] has 1 record. But it gives me this: +--------+---------+---------+---------+----------------+ |Field_A | Field_B | Field_A | Field_B | Combined_Field | +--------+---------+---------+---------+----------------+ |2 |1 |2 |1 |John, Doe | +--------+---------+---------+---------+----------------+ |2 |2 |2 | |, | +--------+---------+---------+---------+----------------+ Really weird is that the [Combined_Field] has a comma in the second row. I use a comma to concatenate two fields in [qry_Table2_Combined]. If the left join query uses a table created from the query [qry_Table2_Combined] it works as expected. Why does this left join query not give the same result for a query and a table? And how can i get the right results using a query in the left join?

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  • Select statement with multiple 'where' fields using same value without duplicating text

    - by kdbdallas
    I will start by saying that I don't think what I want can be done, but that said, I am hoping I am wrong and someone knows more than me. So here is your chance... Prove you are smarter than me :) I want to do a search against a SQLite table looking for any records that "are similar" without having to write out the query in long hand. To clarify this is how I know I can write the query: select * from Articles where title like '%Bla%' or category like '%Bla%' or post like '%Bla%' This works and is not a huge deal if you are only checking against a couple of columns, but if you need to check against a bunch then your query can get really long and nasty looking really fast, not to mention the chance for typos. (ie: 'Bla%' instead of '%Bla%') What I am wondering is if there is a short hand way to do this? *This next code does not work the way I want, but just shows kind of what I am looking for select * from Articles where title or category or post like '%Bla%' Anyone know if there is a way to specify that multiple 'where' columns should use the same search value without listing that same search value for every column? Thanks in advance!

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  • Order by is not working

    - by coure06
    With Results as ( SELECT Top(100) percent ROW_NUMBER() over (Order by (select 1)) as RowNumber, Ad.Date, Title FROM Ad inner join Job on Ad.Id = Job.AdId Order by case When @sortCol='Date' and @sortDir='ASC' Then Date End ASC, case When @sortCol='Date' and @sortDir='DESC' Then Date End DESC ) Select * from Results Where RowNumber BETWEEN @FirstRow AND @LastRow END Whatever is passed in @sortDir and @sortCol it does not work.What am I doing wrong?

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  • Oracle (Old?) Joins - A tool/script for conversion?

    - by Grasper
    I have been porting oracle selects, and I have been running across a lot of queries like so: SELECT e.last_name, d.department_name FROM employees e, departments d WHERE e.department_id(+) = d.department_id; ...and: SELECT last_name, d.department_id FROM employees e, departments d WHERE e.department_id = d.department_id(+); Are there any guides/tutorials for converting all of the variants of the (+) syntax? What is that syntax even called (so I can scour google)? Even better.. Is there a tool/script that will do this conversion for me (Preferred Free)? An optimizer of some sort? I have around 500 of these queries to port.. When was this standard phased out? Any info is appreciated.

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  • Handling apostrophes, php and pgsql

    - by running4surival
    For my forms, I'm using pg_escape_string on every field before I insert them into the database. So I get something like firstname='O''reilly'. But when I try to print that out, I get O''reily, 2 apostrophes. Shouldn't it only 1 apostrophe, O'reilly? This isnt a debugging problem, im just wondering if you have firstname='O''reilly', how do you print that so it is just O'reilly instead of O''reilly?

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  • What is the equivalent of REGEXP_SUBSTR in mysql?

    - by KandadaBoggu
    I want to extract a word from a string column of a table. description =========================== abc order_id: 2 xxxx yyy aa mmm order_id: 3 nn kk yw Expected result set order_id =========================== 2 3 Table will at most have 100 rows, text length is ~256 char and column always has one order_id present. So performance is not an issue. In Oracle, I can use REGEXP_SUBSTR for this problem. How would I solve this in MySQL?

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  • When should we use Views, Temporary Tables and Direct Queries ? What are the Performance issues in a

    - by Shantanu Gupta
    I want to know the performance of using Views, Temp Tables and Direct Queries Usage in a Stored Procedure. I have a table that gets created every time when a trigger gets fired. I know this trigger will be fired very rare and only once at the time of setup. Now I have to use that created table from triggers at many places for fetching data and I confirms it that no one make any changes in that table. i.e ReadOnly Table. I have to use this tables data along with multiple tables to join and fetch result for further queries say select * from triggertable By Using temp table select ... into #tx from triggertable join t2 join t3 and so on select a,b, c from #tx --do something select d,e,f from #tx ---do somethign --and so on --around 6-7 queries in a row in a stored procedure. By Using Views create view viewname ( select ... from triggertable join t2 join t3 and so on ) select a,b, c from viewname --do something select d,e,f from viewname ---do somethign --and so on --around 6-7 queries in a row in a stored procedure. This View can be used in other places as well. So I will be creating at database rather than at sp By Using Direct Query select a,b, c from select ... into #tx from triggertable join t2 join t3 join ... --do something select a,b, c from select ... into #tx from triggertable join t2 join t3 join ... --do something . . --and so on --around 6-7 queries in a row in a stored procedure. Now I can create a view/temporary table/ directly query usage in all upcoming queries. What would be the best to use in this case.

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  • Why MSSQL keeps throwing me Exceptions?

    - by Augusto Càzares
    I have my project in .NET that uses a db in MSSQL Server,i'm using LINQ , sometimes when the projec throws me an exception (Constraint) in a part of the project this same error keeps showing in other part of the project when i do another thing with the db, like when i do an insertion and i had before an exception on delete the insertion throws me the delete exeption, and it remainds this way until i close and open again the project, my major problem is when this happen in my online project, this error in my project causes me problems in the project i'm testing online (i use the same db). I don't know if this exception is on the memory or something but its have been causing me a lot of headechs.

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  • INSERT data from Textbox to Postgres SQL

    - by user1479013
    I just learn how to connect C# and PostgresSQL. I want to INSERT data from tb1(Textbox) and tb2 to database. But I don't know how to code My previous code is SELECT from database. this is my code private void button1_Click(object sender, EventArgs e) { bool blnfound = false; NpgsqlConnection conn = new NpgsqlConnection("Server=127.0.0.1;Port=5432;User Id=postgres;Password=admin123;Database=Login"); conn.Open(); NpgsqlCommand cmd = new NpgsqlCommand("SELECT * FROM login WHERE name='" + tb1.Text + "' and password = '" + tb2.Text + "'",conn); NpgsqlDataReader dr = cmd.ExecuteReader(); if (dr.Read()) { blnfound = true; Form2 f5 = new Form2(); f5.Show(); this.Hide(); } if (blnfound == false) { MessageBox.Show("Name or password is incorrect", "Message Box", MessageBoxButtons.OK, MessageBoxIcon.Exclamation, MessageBoxDefaultButton.Button1); dr.Close(); conn.Close(); } } So please help me the code.

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  • Equivalent of Switch Statement in MySql 5

    - by Robert Gowland
    Using MySql 5, I have a task where I need to update one table based on the contents of another table. For example, I need to add 'A1' to table 'A' if table 'B' contains 'B1'. I need to add 'A2a' and 'A2b' to table 'A' if table 'B' contains 'B2', etc.. In our case, the value in table 'B' we're interested is an enum. Right now I have a stored procedure containing a series of statements like: INSERT INTO A SELECT 'A1' FROM B WHERE B.Value = 'B1'; --Repeat for 'B2' -> 'A2a', 'A2b'; 'B3' -> 'A3', etc... Is there a nicer more DRY way of accomplishing this?

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