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Explicit vs implicit SQL joins
...e joined and how they are joined. Try compare larger SQL queries where you selecting from 8 different tables and you have lots of filtering in the where. By using join syntax you separate out the parts where the tables are joined, to the part where you are filtering the rows.
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What are the Ruby Gotchas a newbie should be warned about? [closed]
...as constants, so local variables should begin with a lowercase letter.
The characters $ and @ do not indicate variable data type as in Perl, but rather function as scope resolution operators.
To denote floating point numbers, one must follow with a zero digit (99.0) or an explicit conversion (99.to_...
Is there any performance gain in indexing a boolean field?
...
It depends on the actual queries and the selectivity of the index/query combination.
Case A: condition WHERE isok = 1 and nothing else there:
SELECT *
FROM tableX
WHERE isok = 1
If the index is selective enough (say you have 1M rows and only 1k have isok = 1), ...
How can I selectively escape percent (%) in Python strings?
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>>> test = "have it break."
>>> selectiveEscape = "Print percent %% in sentence and not %s" % test
>>> print selectiveEscape
Print percent % in sentence and not have it break.
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iOS app with framework crashed on device, dyld: Library not loaded, Xcode 6 Beta
...r Products folder in your project.
Right click on your .framework and select "Show in Finder".
3) Place framework in your project
Drag and drop the .framework from your Finder window to your app project's "Framework" folder.
4) Configure app project for framework
Select the top leve...
Querying data by joining two tables in two database on different servers
...just prefixing the database name with the other server. I.E:
-- FROM DB1
SELECT *
FROM [MyDatabaseOnDB1].[dbo].[MyTable] tab1
INNER JOIN [DB2].[MyDatabaseOnDB2].[dbo].[MyOtherTable] tab2
ON tab1.ID = tab2.ID
Once the link is established, you can also use OPENQUERY to execute a SQL st...
How to determine the encoding of text?
I received some text that is encoded, but I don't know what charset was used. Is there a way to determine the encoding of a text file using Python? How can I detect the encoding/codepage of a text file deals with C#.
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How to load program reading stdin and taking parameters in gdb?
... I figured it out. For some reason I typed void main(int argc, char *argv[]) instead of "int main..." and it slipped my eye. Anyways everything works fine now; thanks for your help!
– vinc456
Jan 18 '09 at 19:04
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Replace new lines with a comma delimiter with Notepad++?
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Open the find and replace dialog (press CTRL+H).
Then select Regular expression in the 'Search Mode' section at the bottom.
In the Find what field enter this: [\r\n]+
In the Replace with: ,
There is a space after the comma.
This will also replace lines like
Apples
Apri...
Entity Framework and SQL Server View
...mn as a primary key, use NULLIF.
An easy way to apply this is to wrap the select statement of your view in another select.
Example:
SELECT
ISNULL(MyPrimaryID,-999) MyPrimaryID,
NULLIF(AnotherProperty,'') AnotherProperty
FROM ( ... ) AS temp
...