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belongs_to through associations
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I'd like to know myself. Everything I tried fired 3 selects. You can specify a "-> { joins :something }" lambda on an association. The join is fired but subsequently another select anyway. I wasn't able to tune this up.
– Renra
Oct 21 ...
Insert auto increment primary key to existing table
...etrieve it by id immediately, MySQL offers LAST_INSERT_ID() for that value SELECT * FROM table_name WHERE id = LAST_INSERT_ID() and most programming language APIs offer some function/method to return that value in the application code.
– Michael Berkowski
Jan 2...
Cannot drop database because it is currently in use
...ar(50)
SET @DatabaseName = N'YOUR_DABASE_NAME'
DECLARE @SQL varchar(max)
SELECT @SQL = COALESCE(@SQL,'') + 'Kill ' + Convert(varchar, SPId) + ';'
FROM MASTER..SysProcesses
WHERE DBId = DB_ID(@DatabaseName) AND SPId <> @@SPId
--SELECT @SQL
EXEC(@SQL)
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What are the use cases for selecting CHAR over VARCHAR in SQL?
...'123 Main St Washington, MD 12345', 123.45)
create view vwStagingTable AS
SELECT CustomerFirstName = CAST(CustomerFirstName as CHAR(30)),
CustomerLastName = CAST(CustomerLastName as CHAR(30)),
CustomerCityStateZip = CAST(CustomerCityStateZip as CHAR(100)),
CustomerCurrentBalance = CAST(CAST(Custome...
Alter column, add default constraint
...e bla add constraint dt_bla default 1 for id
insert bla default values
select * from bla
also make sure you name the default constraint..it will be a pain in the neck to drop it later because it will have one of those crazy system generated names...see also How To Name Default Constraints And ...
Is there an auto increment in sqlite?
... In case it is not obvious from answer, you can use ROWID in your select statement e.g. select rowid from people;
– Colin D
Mar 20 '17 at 15:37
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How to find what code is run by a button or element in Chrome using Developer Tools
... tab, and on the right find Event
Listener Breakpoints:
Expand Mouse and select click
Now click the element (execution should pause), and you are now debugging the code. You can go through all code pressing F11 (which is Step in). Or go back a few jumps in the stack. There can be a ton of jumps
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Database Design for Revisions?
...ke this...
CREATE VIEW EmployeeHistory
AS
, FirstName, , DepartmentId
SELECT EmployeeId, RevisionXML.value('(/employee/FirstName)[1]', 'varchar(50)') AS FirstName,
RevisionXML.value('(/employee/LastName)[1]', 'varchar(100)') AS LastName,
RevisionXML.value('(/employee/DepartmentId)[1]', 'i...
DropDownList's SelectedIndexChanged event not firing
I have a DropDownList object in my web page. When I click on it and select a different value, nothing happens, even though I have a function wired up to the SelectedIndexChanged event.
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How to deal with “java.lang.OutOfMemoryError: Java heap space” error?
...h performance code.
Use local variables wherever possible.
Make sure you select the correct object (EX: Selection between String, StringBuffer and StringBuilder)
Use a good code system for your program(EX: Using static variables VS non static variables)
Other stuff which could work on your code.
T...