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MySQL ON vs USING?
...n tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exact same name on which they join. In this case, one may say:
SELECT ... FR...
how do i remove a comma off the end of a string?
...sponding ltrim for left trim) is very useful as you can specify a range of characters to remove, i.e. to remove commas and trailing whitespace you would write:
$string = rtrim($string, ", \t\n");
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extract part of a string using bash/cut/split
...gs based on position using numbers:
${MYVAR:3} # Remove the first three chars (leaving 4..end)
${MYVAR::3} # Return the first three characters
${MYVAR:3:5} # The next five characters after removing the first 3 (chars 4-9)
You can also replace particular strings or patterns using:
${MYVAR/sear...
SQL join: selecting the last records in a one-to-many relationship
... want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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What is the max size of localStorage values?
... Doesn't crash Chrome anymore... Interesting point: 5MB equals 2.5 Million chars on Chrome. So apparently, UFT16 is used for localStore.
– Felix Alcala
Sep 3 '11 at 17:10
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How do I get extra data from intent on Android?
...TRING);
getArguments().getBoolean(ARG_SECTION_BOOL);
getArguments().getChar(ARG_SECTION_CHAR);
getArguments().getByte(ARG_SECTION_DATA);
}
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SELECT * FROM X WHERE id IN (…) with Dapper ORM
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Dapper supports this directly. For example...
string sql = "SELECT * FROM SomeTable WHERE id IN @ids"
var results = conn.Query(sql, new { ids = new[] { 1, 2, 3, 4, 5 }});
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When should one use a 'www' subdomain?
...nce to its web service?
What would you rather write/type/say.. "www." (4 chars) or "http://" (7 chars) ??
"www." is an established shorthand way of unambiguously communicating the fact that the subject is a web address, not a URL for another network service.
When verbally communicating a web add...
Type erasure techniques
...
I would also consider (similar to void*) the use of "raw storage": char buffer[N].
In C++0x you have std::aligned_storage<Size,Align>::type for this.
You can store anything you want in there, as long as it's small enough and you deal with the alignment properly.
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Set select option 'selected', by value
I have a select field with some options in it. Now I need to select one of those options with jQuery. But how can I do that when I only know the value of the option that must be selected?
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