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On duplicate key ignore? [duplicate]
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Would suggest NOT using INSERT IGNORE as it ignores ALL errors (ie its a sloppy global ignore).
Instead, since in your example tag is the unique key, use:
INSERT INTO table_tags (tag) VALUES ('tag_a'),('tab_b'),('tag_c') ON DUPLICATE KEY UPDATE tag=tag;
on duplicate key pro...
How to empty (clear) the logcat buffer in Android [duplicate]
...rooted buffers (main, system ..etc).
adb logcat -c
If you want to clear all the buffers (like radio, kernel..etc), Please use the following commands
adb root
adb logcat -b all -c
or
adb root
adb shell logcat -b all -c
Use the following commands to know the list of buffers that device supp...
BeautifulSoup getting href [duplicate]
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You can use find_all in the following way to find every a element that has an href attribute, and print each one:
from BeautifulSoup import BeautifulSoup
html = '''<a href="some_url">next</a>
<span class="class"><a href...
How can I trim all strings in an Array? [duplicate]
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@ime: that's what it expected to return actually. Garbage-in garbage-out paradigm in action.
– zerkms
Jun 17 '14 at 10:50
4
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How to create user for a db in postgresql? [closed]
I have installed PostgreSQL 8.4 on my CentOS server and connected to root user from shell and accessing the PostgreSQL shell.
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How to check postgres user and password? [closed]
... you may create a new user or set a new password to the existing user.
Usually, you can login as the postgres user:
Open a Terminal and do sudo su postgres.
Now, after entering your admin password, you are able to launch psql and do
CREATE USER yourname WITH SUPERUSER PASSWORD 'yourpassword';
T...
Advantages of Binary Search Trees over Hash Tables
... instance, if a hash function has a range R(h) = 0...100, then you need to allocate an array of 100 (pointers-to) elements, even if you are just hashing 20 elements. If you were to use a binary search tree to store the same information, you would only allocate as much space as you needed, as well as...
Interface vs Abstract Class (general OO)
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While your question indicates it's for "general OO", it really seems to be focusing on .NET use of these terms.
In .NET (similar for Java):
interfaces can have no state or implementation
a class that implements an interface must provide an implementation of all the methods of tha...