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How to check if a column exists in a SQL Server table?
...Smith didn't knew that, I was using your answer and came across this. Generally I use square brackets during adding columns, so I used them inside COL_LENGTH function too. My code was like this: Alter table Table_Name Add [ColumnName] NVarchar(max) NULL; Select COL_LENGTH('[TABLE_NAME]', '[COLUMN_...
Improve INSERT-per-second performance of SQLite
...more memory will be used for your database.
If you have indices, consider calling CREATE INDEX after doing all your inserts. This is significantly faster than creating the index and then doing your inserts.
You have to be quite careful if you have concurrent access to SQLite, as the whole database i...
How to Programmatically Add Views to Views
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Calling addView is the correct answer, but you need to do a little more than that to get it to work.
If you create a View via a constructor (e.g., Button myButton = new Button();), you'll need to call setLayoutParams on the n...
Joins are for lazy people?
...r developer who claimed to me that JOINs (SQL) are useless. This is technically true but he added that using joins is less efficient than making several requests and link tables in the code (C# or Java).
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How to increment a datetime by one day?
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All of the current answers are wrong in some cases as they do not consider that timezones change their offset relative to UTC. So in some cases adding 24h is different from adding a calendar day.
Proposed solution
The follo...
Can you use CSS to mirror/flip text?
...ds compliant answer, unfortunately we don't live in a world where this actually works for all use cases yet.
– Chris Sobolewski
Oct 20 '13 at 2:10
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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
...00000000040ED948]:
# tracemem[00000000040ED948 -> 00000000040ED830]: .Call copy $<-.data.table $<-
.Internal(inspect(DT))
# @0000000003B7E2A0 19 VECSXP g0c7 [OBJ,NAM(2),TR,ATT] (len=2, tl=100)
# @00000000040C2288 14 REALSXP g0c2 [NAM(2)] (len=2, tl=0) 1,2
# @00000000040C2250 14 REALS...
How do you get the rendered height of an element?
...for everyone's participation. Lots of good info on this thread. This will allow me to center pages using CSS but use jQuery to make the overall height of the "container" div correct without venturing into CSS hackville. Thanks again.
– BuddyJoe
Feb 9 '09 at 17...
Convert a byte array to integer in Java and vice versa
I want to store some data into byte arrays in Java. Basically just numbers which can take up to 2 Bytes per number.
8 Answe...
What are “connecting characters” in Java identifiers?
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I'm not sure that actually fully answers the (implied) question of which characters may start a Java identifier. Following links we end up at Character.isJavaIdentifierStart() which states A character may start a Java identifier if and only if one...