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SQL - Select first 10 rows only?
How do I select only the first 10 results of a query?
12 Answers
12
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Select first row in each GROUP BY group?
As the title suggests, I'd like to select the first row of each set of rows grouped with a GROUP BY .
17 Answers
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Convert a list of characters into a string
If I have a list of chars:
9 Answers
9
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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...
Is bool a native C type?
...C90.
Here's a list of keywords in standard C (not C99):
auto
break
case
char
const
continue
default
do
double
else
enum
extern
float
for
goto
if
int
long
register
return
short
signed
static
struct
switch
typedef
union
unsigned
void
volatile
while
Here's an article discussing some other differen...
Which selector do I need to select an option by its text?
I need to check if a <select> has an option whose text is equal to a specific value.
16 Answers
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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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HTML entity for the middle dot
...
There's actually six variants of this:
char description unicode html html entity utf-8
· Middle Dot U+00B7 &#183; &middot; C2 B7
• Bullet U+2022 &#8226; &bull; ...
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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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 ...