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If table exists drop table then create it, if it does not exist just create it
...up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK('__upgrade'); allows to just invoke all statements sequentially without error checking, but I don't think it's a good idea: complexity increases and locking functions in M...
What's the difference between VARCHAR and CHAR?
...CHAR(10),
Street VARCHAR(10));
Insert into temp
values('Pune','Oxford');
select length(city), length(street) from temp;
Output will be
length(City) Length(street)
10 6
Conclusion: To use storage space efficiently must use VARCHAR Instead CHAR if variable length is ...
How to get default gateway in Mac OSX
...the first line; one with default at its first column.
To display only the selected lines of result, we can use grep command along with netstat
netstat -rn | grep 'default'
This command filters and displays those lines of result having default. In this case, you can see result like following:
de...
Change C++/CLI project to another framework than 4.0 with vs2010
... the Platform Toolset setting in the General property page. You must then select "v90" to get a proper build that targets 3.5. It is however clumsy, you must have all intermediate versions of VS installed on the machine to have that selection available.
Why you need VS2008 installed requires an e...
Cannot convert lambda expression to type 'string' because it is not a delegate type [duplicate]
...ID == Value
orderby q.RowID descending
select q).FirstOrDefault();
Errors:
Error 241 Cannot convert lambda expression to type 'string' because it is not a delegate type
Error 242 Delegate 'System.Func<..>' does not take 1 arguments
Error 243 The name 'Valu...
Find index of a value in an array
... return -1;
}
And you can use LINQ as well:
int keyIndex = words
.Select((v, i) => new {Word = v, Index = i})
.FirstOrDefault(x => x.Word.IsKey)?.Index ?? -1;
share
|
improve thi...
Why all the Active Record hate? [closed]
...need to write raw SQL, it's easily done.
@Tim Sullivan
...and you select several instances of the model, you're basically doing a "select * from ..."
Code:
people = Person.find(:all, :select=>'name, id')
This will only select the name and ID columns from the database, all the other ...
Python function overloading
...working with languages that can discriminate data types at
compile-time, selecting among the alternatives can occur at
compile-time. The act of creating such alternative functions for
compile-time selection is usually referred to as overloading a
function. (Wikipedia)
Python is a dynamical...
How to correctly display .csv files within Excel 2013?
... to DATA tab.
Click button From Text in the General External Data section.
Select your CSV file.
Follow the Text Import Wizard. (in step 2, select the delimiter of your text)
http://blogmines.com/blog/how-to-import-text-file-in-excel-2013/
...
Multiple cases in switch statement
...
This syntax is from the Visual Basic Select...Case Statement:
Dim number As Integer = 8
Select Case number
Case 1 To 5
Debug.WriteLine("Between 1 and 5, inclusive")
' The following is the only Case clause that evaluates to True.
Case 6, ...