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Switch on Enum in Java [duplicate]
...r speed, the switch statement approach might be faster because it's just a table lookup in the bytecode. With your approach, you have to push a new function onto the stack. It's a micro-optimization, but if speed is super important it's something to keep in mind.
– DIMMSum
...
MIN/MAX vs ORDER BY and LIMIT
...king at an unindexed field, using MIN() requires a single full pass of the table. Using SORT and LIMIT requires a filesort. If run against a large table, there would likely be a significant difference in percieved performance. As a meaningless data point, MIN() took .36s while SORT and LIMIT took...
Scheduling R Script
..., to run scheduler first install below packages
install.packages('data.table')
install.packages('knitr')
install.packages('miniUI')
install.packages('shiny')
install.packages("taskscheduleR", repos = "http://www.datatailor.be/rcube", type =
"source")
After installing go to
**TOOLS...
Explicitly set Id with Doctrine when using “AUTO” strategy
...
In case the entity is part of a class table inheritance you need to change the id-generator in the class metadata for both entities (the entity you are persisting and the root entity)
sha...
Include jQuery in the JavaScript Console
... it? For example, on a website I would like to get the number of rows in a table. I know this is really easy with jQuery.
2...
How to create a HashMap with two keys (Key-Pair, Value)?
...mply use:
Map<Key, V> map = //...
and:
map.get(new Key(2, 5));
Table from Guava
Table<Integer, Integer, V> table = HashBasedTable.create();
//...
table.get(2, 5);
Table uses map of maps underneath.
N dimensions
Notice that special Key class is the only approach that scales to...
Are database triggers evil? [closed]
...
They are completely Global - they apply no matter what the context of the table activity;
They are stealthy; it's easy to forget they are there until they hurt you with unintended (and very mysterious) consequences.
This just means they need to be carefully used for the proper circumstances; whi...
PostgreSQL: How to make “case-insensitive” query
...indexes to no longer be seekable. If this is a large or frequently queried table, that could cause trouble. Case-insensitive collation, citext, or a function-based index will improve performance.
– Jordan
Aug 10 '11 at 4:23
...
How do I conditionally apply CSS styles in AngularJS?
...
I have found problems when applying classes inside table elements when I had one class already applied to the whole table (for example, a color applied to the odd rows <myClass tbody tr:nth-child(even) td>). It seems that when you inspect the element with Developer Tool...
Using current time in UTC as default value in PostgreSQL
...ded. Just put parentheses around the default expression:
create temporary table test(
id int,
ts timestamp without time zone default (now() at time zone 'utc')
);
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