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How do I find out my MySQL URL, host, port and username?
...If you're already logged into the command line client try this:
mysql> select user();
It will output something similar to this:
+----------------+
| user() |
+----------------+
| root@localhost |
+----------------+
1 row in set (0.41 sec)
In my example above, I was logged in as root...
How to insert a line break in a SQL Server VARCHAR/NVARCHAR string
...NVARCHAR(100)
SET @text = 'This is line 1.' + CHAR(13) + 'This is line 2.'
SELECT @text
This prints out the following:
This is line 1.
This is line 2.
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Cast int to varchar
...datatype, there is no varchar datatype that you can cast/convert data to:
select CAST(id as CHAR(50)) as col1
from t9;
select CONVERT(id, CHAR(50)) as colI1
from t9;
See the following SQL — in action — over at SQL Fiddle:
/*! Build Schema */
create table t9 (id INT, name VARCHAR(55));
ins...
How to use android emulator for testing bluetooth application?
... virtual machine set the network adapter to 'Bridged'. ·
Start the VM and select 'Live CD VESA' at boot.
Now you need to find out the IP of this VM. Go to terminal in VM (use Alt+F1
& Alt+F7 to toggle) and use the netcfg command to find this.
Now you need open a command prompt and go to your ...
Practical uses of different data structures [closed]
...ght accent at all. You need to understand not just which data structure to select, but some other points to consider when people think about data structures:
pros and cons of the common data structures
why each data structure exist
how it actually work in the memory
specific questions/exe...
Replace duplicate spaces with a single space in T-SQL
...
Even tidier:
select string = replace(replace(replace(' select single spaces',' ','<>'),'><',''),'<>',' ')
Output:
select single spaces
...
How to test an SQL Update statement before running it?
...yway) you can also do a sanity check which rows are affected by running a select using the same WHERE clause as the UPDATE.
So if you UPDATE is
UPDATE foo
SET bar = 42
WHERE col1 = 1
AND col2 = 'foobar';
The following will show you which rows will be updated:
SELECT *
FROM foo
WHERE col1 ...
Bitwise operation and usage
...(where n is the bit number, and 0 is the least significant bit):
unsigned char a |= (1 << n);
Clear a bit:
unsigned char b &= ~(1 << n);
Toggle a bit:
unsigned char c ^= (1 << n);
Test a bit:
unsigned char e = d & (1 << n);
Take the case of your list for exampl...
How to close TCP and UDP ports via windows command line
...don't think that was being asked here. I believe the question is "how do I selectively close one active connection (socket) to the port my program is listening on?". The wording of the question is a bit off because a port number for the undesired inbound client connection is given and it was referr...
How to remove leading and trailing whitespace in a MySQL field?
...d the use case before using this solution:
trim does not work while doing select query
This works
select replace(name , ' ','') from test;
While this doesn't
select trim(name) from test;
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