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How to select html nodes by ID with jquery when the id contains a dot?
...
@Tomalak in comments:
since ID selectors must be preceded by a hash #, there should be no ambiguity here
“#id.class” is a valid selector that requires both an id and a separate class to match; it's valid and not always totally redundant.
The correct...
How do I escape a reserved word in Oracle?
In TSQL I could use something like Select [table] from tablename to select a column named "table".
5 Answers
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Equals(=) vs. LIKE
... can produce results different from the = comparison operator:
mysql> SELECT 'ä' LIKE 'ae' COLLATE latin1_german2_ci;
+-----------------------------------------+
| 'ä' LIKE 'ae' COLLATE latin1_german2_ci |
+-----------------------------------------+
| 0 |...
What is the PostgreSQL equivalent for ISNULL()
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SELECT CASE WHEN field IS NULL THEN 'Empty' ELSE field END AS field_alias
Or more idiomatic:
SELECT coalesce(field, 'Empty') AS field_alias
share...
Overloaded method selection based on the parameter's real type
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I expect the method selection to take
in consideration the real (not the
declared) parameter type. Am I missing
something?
Yes. Your expectation is wrong. In Java, dynamic method dispatch happens only for the object the method is called ...
How to get last N records with activerecord?
...e-wise - at least not up to Rails 3.1. SomeModel.last(5) will execute the select statement without a limit, returning all records of SomeModel to Ruby as an array, after which Ruby will pick out the last (5) elements. Efficiency-wise, currently, you want to use limit - particularly if you have pote...
How to achieve code folding effects in Emacs?
...on: C-h k C-x $
tells us that the above key combination is calling
set-selective-display, a function that takes one numerical argument
(the M-1 prefix passes 1 as the value of that argument) and,
unsurprisingly, sets the variable selective-display to the value of
that argument.
from mino...
LINQ's Distinct() on a particular property
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(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)
{
HashSet<TKey> seenKeys = new HashSet<TKey>();
foreach (TSource element in source)
{
if (seenKeys.Add(keySelector(element)))
{
yield return element;
}
...
Pad a string with leading zeros so it's 3 characters long in SQL Server 2008
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If the field is already a string, this will work
SELECT RIGHT('000'+ISNULL(field,''),3)
If you want nulls to show as '000'
It might be an integer -- then you would want
SELECT RIGHT('000'+CAST(field AS VARCHAR(3)),3)
As required by the question this answer only w...
How to drop column with constraint?
...ing of constraints script:
DECLARE @sql NVARCHAR(MAX)
WHILE 1=1
BEGIN
SELECT TOP 1 @sql = N'alter table tbloffers drop constraint ['+dc.NAME+N']'
from sys.default_constraints dc
JOIN sys.columns c
ON c.default_object_id = dc.object_id
WHERE
dc.parent_object_id = OBJ...
