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How to select from subquery using Laravel Query Builder?
... Note that if you have a complex query as a belongsToMany as subselect you have to add getQuery() twice => $sub->getQuery()->getQuery()
– Jordi Puigdellívol
Aug 28 '15 at 14:23
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Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
can we use xpath with BeautifulSoup?
...tree.HTMLParser()
tree = etree.parse(response, htmlparser)
tree.xpath(xpathselector)
There is also a dedicated lxml.html() module with additional functionality.
Note that in the above example I passed the response object directly to lxml, as having the parser read directly from the stream is more...
How do I delete rows in a data frame?
... :
mydata[-seq(2, nrow(mydata), by = 2) , ]
Or if you want to subset by selecting odd numbers:
mydata[which(1:nrow(mydata) %% 2 == 1) , ]
Or if you want to subset by selecting odd numbers, version 2:
mydata[which(1:nrow(mydata) %% 2 != 0) , ]
Or if you want to subset by filtering even numbe...
Encrypt & Decrypt using PyCrypto AES 256
...code's scope - hashing is just a guarantee that the key is usable with the selected cipher.
– zwer
Jun 20 '17 at 20:35
2
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Logging raw HTTP request/response in ASP.NET MVC & IIS7
...to be able to log the requests and response in as close as possible to the raw, on-the-wire format (i.e including HTTP method, path, all headers, and the body) into a database.
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What is a smart pointer and when should I use one?
...ointer exception.
OLD ANSWER
A smart pointer is a class that wraps a 'raw' (or 'bare') C++ pointer, to manage the lifetime of the object being pointed to. There is no single smart pointer type, but all of them try to abstract a raw pointer in a practical way.
Smart pointers should be preferred...
Rails raw SQL example
...
You can do this:
sql = "Select * from ... your sql query here"
records_array = ActiveRecord::Base.connection.execute(sql)
records_array would then be the result of your sql query in an array which you can iterate through.
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How do I get textual contents from BLOB in Oracle SQL
...S of the text stored in the BLOB, CS of the database used for VARCHAR2) :
select utl_raw.cast_to_varchar2(dbms_lob.substr(BLOB_FIELD)) from TABLE_WITH_BLOB where ID = '<row id>';
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How to save CSS changes of Styles panel of Chrome Developer Tools?
...oper Tools, Right-click in the left panel (where the files are listed) and select Add Folder to Workspace. You can get to a stylesheet in the Sources panel quickly by clicking the stylesheet at the top-right of each CSS rule for a selected element in the Elements panel.
After adding the folder,...