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What does an underscore in front of an import statement mean?
I saw this example from sqlite3 on GitHub :
4 Answers
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In JPA 2, using a CriteriaQuery, how to count results
... the number of results and the actual results which I know is analogous to SQL, but which would make this API a lot more OOP-like. Well, at least I can reuse some of the predicates, I guess.
– Sean Patrick Floyd
May 21 '10 at 18:34
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PostgreSQL query to return results as a comma separated list
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SELECT string_agg(id::text, ',') FROM table
Requires PostgreSQL 9.0 but that's not a problem.
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How can I delete a file from a Git repository?
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git filter-branch -f --index-filter 'git rm --cached --ignore-unmatch *.sql'
Note: Replace *.sql with your file name or file type. Be very careful because this will go through every commit and rip this file type out.
EDIT:
pay attention - after this command you will not be able to push or pul...
Set value to NULL in MySQL
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You're probably quoting 'NULL'. NULL is a reserved word in MySQL, and can be inserted/updated without quotes:
INSERT INTO user (name, something_optional) VALUES ("Joe", NULL);
UPDATE user SET something_optional = NULL;
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What is the difference between an ORM and an ODM?
...bject Document Mapper) deals with documents. Am I right in assuming that mySQL is an example of ORM and MongoDB is a example of ODM?
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MySQL - why not index every field?
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The link is for MS SQL Server; this question is for MySQL
– OMG Ponies
Mar 26 '11 at 23:38
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How to join (merge) data frames (inner, outer, left, right)
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@MattParker I have been using sqldf package for a whole host of complex queries against dataframes, really needed it to do a self-cross join (ie data.frame cross-joining itself) I wonder how it compares from a performance perspective....???
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Fixing slow initial load for IIS
... My problem was that my app was using Windows Integrated Authentication to SQL Server and the service profile was in a different domain than the server. This caused a cross-domain authentication from IIS to SQL upon app initialization - and this was the real source of my delay. I changed to using a ...
How do I escape a reserved word in Oracle?
In TSQL I could use something like Select [table] from tablename to select a column named "table".
5 Answers
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