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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 do SQL EXISTS statements work?
... criteria -- this is why it can be faster than IN. Also be aware that the SELECT clause in an EXISTS is ignored - IE:
SELECT s.*
FROM SUPPLIERS s
WHERE EXISTS (SELECT 1/0
FROM ORDERS o
WHERE o.supplier_id = s.supplier_id)
...should hit a division by zero error...
How do I modify fields inside the new PostgreSQL JSON datatype?
With postgresql 9.3 I can SELECT specific fields of a JSON data type, but how do you modify them using UPDATE? I can't find any examples of this in the postgresql documentation, or anywhere online. I have tried the obvious:
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UITableView Setting some cells as “unselectable”
How can I set the UITableView's cell property to be unselectable? I don't want to see that blue selection box when the user taps on the cell.
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Sublime Text 2 multiple line edit
...t and edit all lines at once.
It's also called "Split into Lines" in the "Selection" menu.
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SQL “select where not in subquery” returns no results
...MySQL
There are three ways to do such a query:
LEFT JOIN / IS NULL:
SELECT *
FROM common
LEFT JOIN
table1 t1
ON t1.common_id = common.common_id
WHERE t1.common_id IS NULL
NOT EXISTS:
SELECT *
FROM common
WHERE NOT EXISTS
(
SELECT NULL
FROM ...
How can I generate an MD5 hash?
... “LATIN1” != “ASCII” (or “US-ASCII”). ASCII is a 7-bit character set, Latin1 is an 8-bit character set. They are not the same.
– Bombe
Jan 7 '09 at 7:57
8
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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 "
#...
Change the selected value of a drop-down list with jQuery
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jQuery's documentation states:
[jQuery.val] checks, or selects, all the radio buttons, checkboxes, and select options that match the set of values.
This behavior is in jQuery versions 1.2 and above.
You most likely want this:
$("._statusDDL").val('2');
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DISTINCT for only one column
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If you are using SQL Server 2005 or above use this:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVER(PARTITION BY Email ORDER BY ...