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What is the difference between “INNER JOIN” and “OUTER JOIN”?
...he intersection of the two tables, i.e. the two rows they have in common.
select * from a INNER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b;
a | b
--+--
3 | 3
4 | 4
Left outer join
A left outer join will give all rows in A, plus any common rows in B.
select * from a LEFT OUT...
Select Multiple Fields from List in Linq
...
Anonymous types allow you to select arbitrary fields into data structures that are strongly typed later on in your code:
var cats = listObject
.Select(i => new { i.category_id, i.category_name })
.Distinct()
.OrderByDescending(i => i.c...
How can I use the $index inside a ng-repeat to enable a class and show a DIV?
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The issue here is that ng-repeat creates its own scope, so when you do selected=$index it creates a new a selected property in that scope rather than altering the existing one. To fix this you have two options:
Change the selected property to a non-primitive (ie object or array, which makes jav...
T-SQL: Deleting all duplicate rows but keeping one [duplicate]
... I do not care about that. I still need to keep one of these rows however. SELECT DISTINCT won't work because it operates on all columns and I need to suppress duplicates based on the key columns.
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Mysql: Select rows from a table that are not in another
How to select all rows in one table that do not appear on another?
8 Answers
8
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SQL - find records from one table which don't exist in another
...shortest statement, and may be quickest if your phone book is very short:
SELECT *
FROM Call
WHERE phone_number NOT IN (SELECT phone_number FROM Phone_book)
alternatively (thanks to Alterlife)
SELECT *
FROM Call
WHERE NOT EXISTS
(SELECT *
FROM Phone_book
WHERE Phone_book.phon...
Why is  appearing in my HTML? [duplicate]
I see this character in Firebug  .
10 Answers
10
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Copying text outside of Vim with set mouse=a enabled
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Press shift while selecting with the mouse. This will make mouse selection behave as if mouse=a was not enabled.
Note: this trick also applies to "middle button paste": if you want to paste in vim text that was selected outside, press shift w...
How can I escape a double quote inside double quotes?
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Use a backslash:
echo "\"" # Prints one " character.
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How to remove all whitespace from a string?
...paces before, after and in between
" \u2190 \u2192 ", # contains unicode chars
paste0( # varied whitespace
whitespace,
"x",
whitespace,
"y",
whitespace,
collapse = ""
),
NA # missing
)
## [1] " x y "
#...