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bundle install returns “Could not locate Gemfile”
I'm new to Rails and am currently working through a guide.
The guide states:
9 Answers
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Best algorithm for detecting cycles in a directed graph [closed]
...grey (current node is visited but all reachable nodes are not yet visited) and black (all reachable nodes are visited along with the current one) color coding, if a grey node finds another grey node then we've a cycle. [Pretty much what we've in Cormen's algorithm book]. Wondering if 'Tarjan's algor...
Avoiding instanceof in Java
...ng a chain of "instanceof" operations is considered a "code smell". The standard answer is "use polymorphism". How would I do it in this case?
...
How do I test a file upload in rails?
I have a controller which is responsible for accepting JSON files and then processing the JSON files to do some user maintenance for our application. In user testing the file upload and processing works, but of course I would like to automate the process of testing the user maintenance in our testin...
Does MySQL foreign_key_checks affect the entire database?
When I execute this command in MySQL:
6 Answers
6
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How do I list all tables in a schema in Oracle SQL?
...NCT OWNER, OBJECT_NAME
FROM DBA_OBJECTS
WHERE OBJECT_TYPE = 'TABLE'
AND OWNER = '[some other schema]'
Without those system privileges, you can only see tables you have been granted some level of access to, whether directly or through a role.
SELECT DISTINCT OWNER, OBJECT_NAME
FROM ALL_O...
Java: Integer equals vs. ==
...r values. Hence the comparison with == only works for numbers between -128 and 127.
Refer: #Immutable_Objects_.2F_Wrapper_Class_Caching
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Can't connect to local MySQL server through socket '/var/mysql/mysql.sock' (38)
...ysql/mysql.sock
you can check if mysql is running with the following command:
mysqladmin -u root -p status
try changing your permission to mysql folder. If you are working locally, you can try:
sudo chmod -R 755 /var/lib/mysql/
that solved it for me
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How to convert comma-separated String to List?
...al comma, zero or more whitespace which will place the words into the list and collapse any whitespace between the words and commas.
Please note that this returns simply a wrapper on an array: you CANNOT for example .remove() from the resulting List. For an actual ArrayList you must further use ...
How can I define a composite primary key in SQL?
...rID)
);
The pair (QuestionID,MemberID) must then be unique for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because...