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How do I get the 'clear' command in Cygwin?
... @AndrewProck It seems to be there now!
– Rohaq
Dec 20 '13 at 17:42
Thanks for this! If you've already installe...
How to COUNT rows within EntityFramework without loading contents?
...ce SQL Server really can't do anything but do a full table scan (clustered index scan).
Sometimes, it's good enough to know an approximate number of rows from the database, and in such a case, a statement like this might suffice:
SELECT
SUM(used_page_count) * 8 AS SizeKB,
SUM(row_count) ...
Unable to find the wrapper “https” - did you forget to enable it when you configured PHP?
The problem is in the question. I've done a thorough investigation for solutions in regards to this and I know there are topics to this and I've followed them too and nothing has worked. That being said I'll list out exactly everything I've done so far. I am running PHP 5.2.14 with Zend Debugging on...
Best way to test if a row exists in a MySQL table
...on in the comments, that in this situation:
SELECT 1 FROM my_table WHERE *indexed_condition* LIMIT 1
Is superior to:
SELECT * FROM my_table WHERE *indexed_condition* LIMIT 1
This is because the first query can be satisfied by the index, whereas the second requires a row look up (unless possibl...
What does ^M character mean in Vim?
... the case the defaults remap the "special character escape" key it to Ctrl+Q.
– R. Martinho Fernandes
May 1 '11 at 17:45
9
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MySQL case insensitive select
...e, comparisons are case-insensitive. You need to understand collations and indexes and configure those properly - using string transformations like LOWER() or an arbitrary COLLATE clause can completely bypass an index, and over time, as your table grows, this can have drastic performance implication...
Difference between partition key, composite key and clustering key in Cassandra?
...y in the order they're set.
so the valid queries are (excluding secondary indexes)
col1 and col2
col1 and col2 and col10
col1 and col2 and col10 and col 4
Invalid:
col1 and col2 and col4
anything that does not contain both col1 and col2
Hope this helps.
...
open() in Python does not create a file if it doesn't exist
...losed at the block's end, even if an exception is raised on the way. It's equivalent to try-finally, but much shorter.
with open("file.dat","a+") as f:
f.write(...)
...
a+ Opens a file for both appending and reading. The file pointer is
at the end of the file if the file exists. The ...
TypeScript Objects as Dictionary types as in C#
... That's a useful way to make sure that the compiler restricts indexes to strings. Interesting. Doesn't look like you can specify the index type to be anything other than strings or integers, but that makes sense, since it just maps to the native JS object indexes.
–...
Remove the last three characters from a string
...ly asked question]
You can use string.Substring and give it the starting index and it will get the substring starting from given index till end.
myString.Substring(myString.Length-3)
Retrieves a substring from this instance. The substring starts at a
specified character position. MSDN
E...