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Difference between natural join and inner join
... definition of a natural join is to join on *all like-named columns*. From MySQL doc: The NATURAL [LEFT] JOIN of two tables is defined to be semantically equivalent to an INNER JOIN or a LEFT JOIN with a USING clause that names all columns that exist in both tables.. And another thing - in practice ...
What is a stored procedure?
... For more detail about stored procedure you can refer my URL techflirt.com/mysql-stored-procedure-tutorial
– Ankur Kumar Singh
Mar 4 '18 at 5:25
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...
Ukkonen's suffix tree algorithm in plain English
...ts.
What we are building, is basically like a search trie. So there
is a root node, edges going out of it leading to new nodes, and
further edges going out of those, and so forth
But: Unlike in a search trie, the edge labels are not single
characters. Instead, each edge is labeled using a pair of ...
Using SSH keys inside docker container
...sh-server \
libmysqlclient-dev
# Authorize SSH Host
RUN mkdir -p /root/.ssh && \
chmod 0700 /root/.ssh && \
ssh-keyscan github.com > /root/.ssh/known_hosts
# Add the keys and set permissions
RUN echo "$ssh_prv_key" > /root/.ssh/id_rsa && \
echo "$s...
What should be in my .gitignore for an Android Studio project?
...uction
*.iws
*.ipr
*~
*.swp
This file should be located in the project's root folder and not inside the project's module folder.
Edit Notes:
Since version 0.3+ it seems you can commit and push *.iml and build.gradle files. If your project is based on Gradle: in the new open/import dialog, you s...
How to pretty print XML from the command line?
...
libxml2-utils
This utility comes with libxml2-utils:
echo '<root><foo a="b">lorem</foo><bar value="ipsum" /></root>' |
xmllint --format -
Perl's XML::Twig
This command comes with XML::Twig perl module, sometimes xml-twig-tools package:
echo '<root...
When to use SELECT … FOR UPDATE?
...ends on the concurrency control your database system is using.
MyISAM in MySQL (and several other old systems) does lock the whole table for the duration of a query.
In SQL Server, SELECT queries place shared locks on the records / pages / tables they have examined, while DML queries place update ...
Get root view from current activity
I know how to get the root view with View.getRootView() . I am also able to get the view from a button's onClick event where the argument is a View . But how can I get the view in an activity ?
...
How should you build your database from source control?
.../setup_db.sql
proj/sql/dummy_data.sql
proj/sql/mssql_specific.sql
proj/sql/mysql_specific.sql
And then I abstract out all my SQL queries so that I can build the entire project for MySQL, Oracle, MSSQL or anything else.
Build and test automation uses these build-scripts as they are as important as...
how to check if a file is a directory or regular file in python? [duplicate]
...def walktree(top, callback):
'''recursively descend the directory tree rooted at top,
calling the callback function for each regular file'''
for f in os.listdir(top):
pathname = os.path.join(top, f)
mode = os.stat(pathname)[ST_MODE]
if S_ISDIR(mode):
...