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sql ORDER BY multiple values in specific order?
...
You can order by a selected column or other expressions.
Here an example, how to order by the result of a case-statement:
SELECT col1
, col2
FROM tbl_Bill
WHERE col1 = 0
ORDER BY -- order by case-statement
CASE WHEN tbl_Bi...
how to check if a form is valid programmatically using jQuery Validation Plugin
... jQuery Validation plugin:
$("#form_id").valid();
Checks whether the selected form is valid or whether all selected
elements are valid. validate() needs to be called on the form before
checking it using this method.
Where the form with id='form_id' is a form that has already had .validat...
Hidden Features of MySQL
...that has an integer type,
you can also refer to the column as "_rowid" in SELECT statements.
In MySQL, the name of a PRIMARY KEY is PRIMARY
Currently, only InnoDB (v5.1?) tables support foreign keys.
Usually, you create all the indexes you need when you are creating tables.
Any column declared...
Are Stored Procedures more efficient, in general, than inline statements on modern RDBMS's? [duplica
...he query plan that is generated is sub-optimal.
For example, if you send SELECT *
FROM table WHERE id BETWEEN 1 AND
99999999, the DBMS may select a
full-table scan instead of an index
scan because you're grabbing every row
in the table (so sayeth the
statistics). If this is the cached
...
Automatic Preferred Max Layout Width is not available on iOS versions prior to 8.0
... my steps below.
In xCode's Issue Navigator right click on the error and select "Reveal In Log". (Note: @Sam suggests below, look in xCode's report navigator. Also @Rivera notes in the comments that "As of Xcode 6.1.1, clicking on the warning will automatically open and highlight the conflicting l...
Github Push Error: RPC failed; result=22, HTTP code = 413
... Information Services (IIS) Manager
Expand the Server field
Expand Sites
Select the site you want to make the modification for.
In the Features section, double click Configuration Editor
Under Section select: system.webServer > serverRuntime
Modify the uploadReadAheadSize section (The value mus...
How to comment out a block of code in Python [duplicate]
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vim with nerdcommenter. Select the block you want and ,c<space>
– dev_nut
Oct 10 '14 at 22:37
add a comment
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data.table vs dplyr: can one do something well the other can't or does poorly?
... ## data.table syntax
left_join(DT2, DT1) ## dplyr syntax
# 2. select columns while join
DT1[DT2, .(z, i.mul)]
left_join(select(DT2, x, y, mul), select(DT1, x, y, z))
# 3. aggregate while join
DT1[DT2, .(sum(z) * i.mul), by = .EACHI]
DF1 %>% group_by(x, y) %>% summarise(z = su...
Could not load file or assembly 'System.Web.Mvc'
...
In VS2010, right click the project in the Solution Explorer and select 'Add Deployable Dependencies'. Then check the MVC related check boxes in the following dialog.
This creates a '_bin_deployableAssemblies' folder in the project which contains all the .dll files mentioned in other answ...
List of ANSI color escape sequences
...
The ANSI escape sequences you're looking for are the Select Graphic Rendition subset. All of these have the form
\033[XXXm
where XXX is a series of semicolon-separated parameters.
To say, make text red, bold, and underlined (we'll discuss many other options below) in C you mig...