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Should try…catch go inside or outside a loop?
...ch structures are placed. Internally, they are implemented as a code-range table in a structure that is created when the method is called. While the method is executing, the try/catch structures are completely out of the picture unless a throw occurs, then the location of the error is compared again...
Dynamic SELECT TOP @var In SQL Server
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SELECT TOP (@count) * FROM SomeTable
This will only work with SQL 2005+
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How to stop text from taking up more than 1 line?
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Note: this only works on block elements. If you need to do this to table cells (for example) you need to put a div inside the table cell as table cells have display table-cell not block.
As of CSS3, this is supported for table cells as well.
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What is the difference between Non-Repeatable Read and Phantom Read?
What is the difference between non-repeatable read and phantom read?
9 Answers
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Omit rows containing specific column of NA
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It is possible to use na.omit for data.table:
na.omit(data, cols = c("x", "z"))
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Are foreign keys really necessary in a database design?
... code using things like ON DELETE CASCADE. This means that if you have one table containing users and another containing orders or something, then deleting a user could automatically delete all orders that point to that user.
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Using an ORM or plain SQL? [closed]
...ased on Java beans get/set methods. This is a TON of boilerplate for every table, for every column and ... here's the real anti-pattern: Just to expose every field as if it were public. In effect, having a get/set method on fields in an object/table/row is very close to violating every tenant of inf...
Subset of rows containing NA (missing) values in a chosen column of a data frame
...t "NA" strings to NA values, and let "NULL" strings as is).
If using read.table() or read.csv(), you should consider the "na.strings" argument to do clean data import, and always work with real R NA values.
An example, working in both cases "NULL" and "NA" cells :
DF <- read.csv("file.csv", na...
Sending a message to nil in Objective-C
...gt; 0 )
or this:
return [myArray count]; // say for number of rows in a table
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Is there an opposite to display:none?
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When changing element's display in Javascript, in many cases a suitable option to 'undo' the result of element.style.display = "none" is element.style.display = "". This removes the display declaration from the style attribute, reverting the actual value of display property to the value set...