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String concatenation in MySQL
I am using MySQL and MySQL Workbench 5.2 CE. When I try to concatenate 2 columns, last_name and first_name , it doesn't work :
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How to upload a file in Django? [closed]
...e Django stores uploaded files and from what URL Django serves them. MEDIA_ROOT and MEDIA_URL are in settings.py by default but they are empty. See the first lines in Django Managing Files for details. Remember also set the database and add myapp to INSTALLED_APPS
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import os
BASE_DIR = os.path....
Which ORM should I use for Node.js and MySQL? [closed]
I'm rewriting a project to use Node.js. I'd like to keep using MySQL as the DB (even though I don't mind rewriting the schema).
I'm looking for a simple-to-use, reasonable-performance ORM, which supports caching, many-to-one and many-to-many relations.
From the MySQL ORMs I could find, persistencej...
How to select date from datetime column?
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You can use MySQL's DATE() function:
WHERE DATE(datetime) = '2009-10-20'
You could also try this:
WHERE datetime LIKE '2009-10-20%'
See this answer for info on the performance implications of using LIKE.
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Get query from java.sql.PreparedStatement [duplicate]
...To my experience, the ones which do so are at least the PostgreSQL 8.x and MySQL 5.x JDBC drivers. For the case your JDBC driver doesn't support it, your best bet is using a statement wrapper which logs all setXxx() methods and finally populates a SQL string on toString() based on the logged informa...
log messages appearing twice with Python Logging
...g is left set to True. A
common scenario is to attach handlers only to the root logger, and to
let propagation take care of the rest.
So, if you want a custom handler on "test", and you don't want its messages also going to the root handler, the answer is simple: turn off its propagate flag:
logger...
How do I escape reserved words used as column names? MySQL/Create Table
...and one problem is a class may have a field name key which is a reserved MySQL keyword. How do I escape it in a create table statement? (Note: The other problem below is text must be a fixed size to be indexed/unique)
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How to find all serial devices (ttyS, ttyUSB, ..) on Linux without opening them?
... system. A trimmed down example:
# ll /sys/class/tty/ttyUSB*
lrwxrwxrwx 1 root root 0 2012-03-28 20:43 /sys/class/tty/ttyUSB0 -> ../../devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.4/2-1.4:1.0/ttyUSB0/tty/ttyUSB0/
lrwxrwxrwx 1 root root 0 2012-03-28 20:44 /sys/class/tty/ttyUSB1 -> ../../device...
Is there an SQLite equivalent to MySQL's DESCRIBE [table]?
... SQLite . It would be nice to be able to see the details for a table, like MySQL's DESCRIBE [table] . PRAGMA table_info [table] isn't good enough, as it only has basic information (for example, it doesn't show if a column is a field of some sort or not). Does SQLite have a way to do this?
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ALTER TABLE to add a composite primary key
...r table you will get an error when trying to drop it. In some versions of mysql the error message there was malformed (as of 5.5.17, this error message is still
alter table parent drop column id;
ERROR 1025 (HY000): Error on rename of
'./test/#sql-a04_b' to './test/parent' (errno: 150).
If you ...