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Optimistic vs. Pessimistic locking
...stay unmodified for the duration, it's as accurate as pessimistic locking (select for update style) on those same records. The main difference is that optimistic locking incurs overhead only if there's a conflict, whereas pessimistic locking has reduced overhead on conflict. So optimistic is best ...
How and when to use ‘async’ and ‘await’
From my understanding one of the main things that async and await do is to make code easy to write and read - but is using them equal to spawning background threads to perform long duration logic?
...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
...rows affected (0.02 sec)
Records: 3 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM tin3;
+----+------------+
| id | val |
+----+------------+
| 1 | 0000000012 |
| 2 | 0000000007 |
| 4 | 0000000101 |
+----+------------+
3 rows in set (0.00 sec)
mysql>
mysql> SELECT LENGTH(val)...
How do I remove a single file from the staging area (undo git add)?
...ve the staged files. Guess I've been looking at that screen so long I was selectively choosing what I wanted to see.
– PHLAK
Oct 1 '09 at 20:34
2
...
How to expand/collapse a diff sections in Vimdiff?
...w as mentioned can be used for navigating from pane to pane.
Now you can select a particular change alone and paste it to the other pane as follows.Here I am giving an eg as if I wanted to change my piece of code from pane 1 to pane 2 and currently my cursor is in pane1
Use Shift-v to highlight ...
AI2 Media Notification
...vailable up from API Level 23. The SmallSystemIcon property to allows to select a system icon for older versions (for possible options see: System Notification Icons). The selection rule is as follows: Condition Selection API Level SmallIconImage SmallSystemIcon ≥ 23 ...
How can I use “puts” to the console without a line break in ruby on rails?
...oothly, you need to flush the stdout buffer after each print...
def print_and_flush(str)
print str
$stdout.flush
end
100.times do
print_and_flush "."
sleep 1
end
Edit: I was just looking into the reasoning behind flush to answer @rubyprince's comment, and realised this could be cleaned u...
Eclipse error: indirectly referenced from required .class files?
...nfigured project)
Remove the "JRE System Library"
Hit "Add Library ...", Select "JRE System Library" and add the appropriate JRE for the project (eg. 'Workspace default JRE')
Hit "Finish" in the library selection and "OK" in the project properties and then wait for the re-build of the project
Ho...
How do I ignore ampersands in a SQL script running from SQL Plus?
..., I've chose the # character, but that choice is just an example.
SQL> select '&var_ampersand #var_hash' from dual;
Enter value for var_ampersand: a value
'AVALUE#VAR_HASH'
-----------------
a value #var_hash
SQL> set define #
SQL> r
1* select '&var_ampersand #var_hash' from du...
unresolved reference to object [INFORMATION_SCHEMA].[TABLES]
...database reference to master:
Under the project, right-click References.
Select Add database reference....
Select System database.
Ensure master is selected.
Press OK.
Note that it might take a while for VS to update.
sh...