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Unpivot with column name
I have a table StudentMarks with columns Name, Maths, Science, English .
Data is like
4 Answers
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Difference between FOR and AFTER triggers?
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There is no difference, they do the same thing.
CREATE TRIGGER trgTable on dbo.Table FOR INSERT,UPDATE,DELETE
Is the same as
CREATE TRIGGER trgTable on dbo.Table AFTER INSERT,UPDATE,DELETE
An INSTEAD OF trigger is different, and fires before and instead of the insert and can be used on...
SQL Server 2008: how do I grant privileges to a username?
I need to be able to establish an ODBC connection through SQL Server authentication.
3 Answers
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Accessing an SQLite Database in Swift
...en it is no longer required.
Use sqlite3_exec to perform SQL (e.g. create table).
if sqlite3_exec(db, "create table if not exists test (id integer primary key autoincrement, name text)", nil, nil, nil) != SQLITE_OK {
let errmsg = String(cString: sqlite3_errmsg(db)!)
print("error creating t...
Is it possible to decrypt MD5 hashes?
...od guess at someone's password by Googling for the hash or using a Rainbow table. That is one reason why you should always "salt" hashed passwords, so that two identical values, when hashed, will not hash to the same value.
Once a piece of data has been run through a hash function, there is no goin...
How do I set a column value to NULL in SQL Server Management Studio?
...roperly answered the question but just to cover all the bases:
Update myTable set MyColumn = NULL
This would set the entire column to null as the Question Title asks.
To set a specific row on a specific column to null use:
Update myTable set MyColumn = NULL where Field = Condition.
This wou...
Is floating point math broken?
...754 is anything with an error of less than one unit in the last place. The table of reciprocals of Y (1/Y) is known as the quotient selection table (QST) in the slow division, and the size in bits of the quotient selection table is usually the width of the radix, or a number of bits of the quotient ...
Repeater, ListView, DataList, DataGrid, GridView … Which to choose?
...t you trying to achieve
Gridview - Limited in design, works like an html table. More in built functionality like edit/update, page, sort. Lots of overhead.
DataGrid - Old version of the Gridview. A gridview is a super datagrid.
Datalist - more customisable version of the Gridview. Also has some o...
How to write a simple database engine [closed]
...f it). I know most of the basic data structures taught in CS (trees, hash tables, lists, etc.) as well as a pretty good understanding of compiler theory (and have implemented a very simple interpreter) but I don't understand how to go about writing a database engine. I have searched for tutorials ...
Difference between attr_accessor and attr_accessible
...hat when you create somehow a link between a (Rails) model with a database table, you NEVER, NEVER, NEVER need attr_accessor in your model to create setters and getters in order to be able to modify your table's records.
This is because your model inherits all methods from the ActiveRecord::Base Cl...