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How do I do top 1 in Oracle?
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261
If you want just a first selected row, you can:
select fname from MyTbl where rownum = 1
You ...
PHP Function with Optional Parameters
I've written a PHP function that can accepts 10 parameters, but only 2 are required. Sometimes, I want to define the eighth parameter, but I don't want to type in empty strings for each of the parameters until I reach the eighth.
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The tilde operator in Python
...complement representation of the integer are reversed (as in b <- b XOR 1 for each individual bit), and the result interpreted again as a twos-complement integer. So for integers, ~x is equivalent to (-x) - 1.
The reified form of the ~ operator is provided as operator.invert. To support this o...
SQL JOIN and different types of JOINs
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331
An illustration from W3schools:
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jQuery deferreds and promises - .then() vs .done()
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10 Answers
10
Active
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Regex exactly n OR m times
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91
There is no single quantifier that means "exactly m or n times". The way you are doing it is fin...
How do you read CSS rule values with JavaScript?
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16 Answers
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Active
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Does MySQL ignore null values on unique constraints?
...ws multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSERT table1 VALUES (NULL);
SELECT * FROM table1;
Result:
x
NULL
NULL
1
This i...
Maintaining the final state at end of a CSS3 animation
...applied onClick, and, using keyframes, it changes the opacity from 0 to 1 (among other things).
4 Answers
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