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What's the fastest way to merge/join data.frames in R?
..., in fact, they are placed on tables which were overwritten before the sql select ever runs and that, in part, accounts for why its so slow. The idea of sqldf is that the data frames in your R session constitute the data base, not the tables in sqlite. Thus each time the code refers to an unqualif...
ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
...table is already locked by some query. For example, you may have executed "select for update" and have not yet committed/rollbacked and fired another select query. Do a commit/rollback before executing your query.
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How to get duplicate items from a list using LINQ? [duplicate]
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var duplicates = lst.GroupBy(s => s)
.SelectMany(grp => grp.Skip(1));
Note that this will return all duplicates, so if you only want to know which items are duplicated in the source list, you could apply Distinct to the resulting sequence or use the solution...
How to get the index of an element in an IEnumerable?
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extensions with overloads like Select((x, i) => ...) seem to imply that these indexes should exist
– Michael
Mar 19 '14 at 16:05
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How to call a stored procedure from Java and JPA
...s (
postId IN NUMBER,
commentCount OUT NUMBER )
AS
BEGIN
SELECT COUNT(*) INTO commentCount
FROM post_comment
WHERE post_id = postId;
END;
You can call it from JPA as follows:
StoredProcedureQuery query = entityManager
.createStoredProcedureQuery("count_comments"...
Find UNC path of a network drive?
...le from Windows Explorer into the body of a Word document or Outlook email
Select 'Create Hyperlink Here'
The inserted text will be the full UNC of the dragged item.
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AI2 SideBar Extension
...iggered. 1.2 (2022-09-01) Graphic files from the asset area can be selected as icons for the sidebar items. 1.3 (2023-06-13) Proprties FontBold, FontItalic, FontTypeface added. 1.4 (2023-06-19) Exception at FontTypeface == default removed. Contents Download Us...
Delete branches in Bitbucket
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in Bitbucket go to branches in left hand side menu.
Select your branch you want to delete.
Go to action column, click on three dots (...) and select delete.
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HTML File Selection Event
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I think @anthony is referring to the following scenario: Select a file. Now open the file selector again, but this time click on Cancel. Since no file was selected the second time, the file input control resets, thus changing its initial selection, and the change event is fired.
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'Java' is not recognized as an internal or external command
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For Windows 7:
Right click on My Computer
Select Properties
Select Advanced System Settings
Select Advanced tab
Select Environment Variables
Select Path under System Variables
Click on Edit button
In Variable value editor paste this at the start of the line
C:\Progr...