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How to edit multi-gigabyte text files? Vim doesn't work =( [closed]
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Great tip. I had a 13GB (152.000.000 lines) sql-file, and just using "split -l 1000000" then editing the one million line files where I wanted with vim worked great. Took 10 minutes just to split them. (I tried to open the original file with vim and that worked, but it...
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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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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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...
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 ...