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What columns generally make good indexes?
...nto your tables:
Only index those columns that are required in WHERE and ORDER BY clauses. Indexing columns in abundance will result in some disadvantages.
Try to take benefit of "index prefix" or "multi-columns index" feature of MySQL. If you create an index such as INDEX(first_name, last_name),...
Callback after all asynchronous forEach callbacks are completed
...ue of the index parameter does not provide the same guarantee, because the order of return of the asynchronous operations is not guaranteed.
Using ES6 Promises
(a promise library can be used for older browsers):
Process all requests guaranteeing synchronous execution (e.g. 1 then 2 then 3)
func...
Query to list number of records in each table in a database
...id <= 1
GROUP BY
t.NAME, i.object_id, i.index_id, i.name, p.[Rows]
ORDER BY
object_name(i.object_id)
In my opinion, it's easier to handle than the sp_msforeachtable output.
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How to export all data from table to an insertable sql format?
...me
, u.ColumnValue
FROM
(SELECT
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS rn,
'
+ CHAR(13) + @ColumnsCast
+ CHAR(13) + 'FROM [' + @SchemaName + '].[' + @TableName + '] s'
+ CHAR(13) + 'WHERE 1 = 1'
+ CHAR(13) + COALESCE(@WhereClause,'')
+ CHAR(13) ...
How can I position my div at the bottom of its container?
...ement seeks it's closest parent that is absolute or relatively position in order to determine it's position. If all fails it resorts to body (window). So hence the need for the parent to be relative.
– user17753
Jun 13 '12 at 18:46
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Get an array of list element contents in jQuery
...
Does jQuery guarantee an order to the elements returned by the query? I would assume that the order returned is the same as the ordering in the DOM (ie text1, text2, text3), but I don't know what to look for in the documentation to see if this is tru...
How to do joins in LINQ on multiple fields in single join
...r a second from clause) IMO. You could do some particularly funky magic by ordering one side or the other to find matches more efficiently, but that would be a lot of work - I'd only do that kind of thing after checking whether performance is an issue.
...
Do I need to explicitly call the base virtual destructor?
...
No, destructors are called automatically in the reverse order of construction. (Base classes last). Do not call base class destructors.
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Array.sort() doesn't sort numbers correctly [duplicate]
...aphical sort (e.g. convert objects to strings, and sort them in dictionary order), which is the default sort behavior in Javascript:
https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/sort
array.sort([compareFunction])
Parameters
compareFunction
Specifies a function that de...
Why is volatile not considered useful in multithreaded C or C++ programming?
...egister instead and defer updating main memory until much later)
that no reordering takes place. Assume that we use a volatile variable as a flag to indicate whether or not some data is ready to be read. In our code, we simply set the flag after preparing the data, so all looks fine. But what if the...