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How to create id with AUTO_INCREMENT on Oracle?
...acle 11g. However, you can model it easily with a sequence and a trigger:
Table definition:
CREATE TABLE departments (
ID NUMBER(10) NOT NULL,
DESCRIPTION VARCHAR2(50) NOT NULL);
ALTER TABLE departments ADD (
CONSTRAINT dept_pk PRIMARY KEY (ID));
CREATE SEQUENCE dept_seq STA...
Is it possible to refresh a single UITableViewCell in a UITableView?
I have a custom UITableView using UITableViewCell s.
Each UITableViewCell has 2 buttons. Clicking these buttons will change an image in a UIImageView within the cell.
...
Colorized Ruby output to the terminal [closed]
...color modes, based on answers by Erik Skoglund and others.
#outputs color table to console, regular and bold modes
def colortable
names = %w(black red green yellow blue pink cyan white default)
fgcodes = (30..39).to_a - [38]
s = ''
reg = "\e[%d;%dm%s\e[0m"
bold = "\e[1;%d;%dm%s\e[0m"
...
Create table in SQLite only if it doesn't exist already
I want to create a table in a SQLite database only if doesn't exist already. Is there any way to do this? I don't want to drop the table if it exists, only create it if it doesn't.
...
How to get a list of user accounts using the command line in MySQL?
...
Use this query:
SELECT User FROM mysql.user;
Which will output a table like this:
+-------+
| User |
+-------+
| root |
+-------+
| user2 |
+-------+
As Matthew Scharley points out in the comments on this answer, you can group by the User column if you'd only like to see unique userna...
How to convert a table to a data frame
I have a table in R that has str() of this:
5 Answers
5
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HTML colspan in CSS
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Tables are structural elements and just because using colspan changes its appearance does not mean it's not. CSS is used to style elements and not change the structure. The W3C discusses table structure here: w3.org/TR/h...
multiprocessing.Pool: When to use apply, apply_async or map?
...
Here is an overview in a table format in order to show the differences between Pool.apply, Pool.apply_async, Pool.map and Pool.map_async. When choosing one, you have to take multi-args, concurrency, blocking, and ordering into account:
...
Big-O summary for Java Collections Framework implementations? [closed]
...s next notes
HashSet O(1) O(1) O(h/n) h is the table capacity
LinkedHashSet O(1) O(1) O(1)
CopyOnWriteArraySet O(n) O(n) O(1)
EnumSet O(1) O(1) O(1)
TreeSet O(log n) O(log n) O(log n)
ConcurrentSkipListSet O...
Add a default value to a column through a migration
...an a change block. You can leave the down block empty. It won't revert the table to the original condition but the migration can be rolled back.
– IAmNaN
May 16 '14 at 1:16
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