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MongoDB and “joins” [duplicate]
...r hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
You can read more about DBRef here:
http://docs.mongodb.org/manual/applications/database-references/
There are two possible solutions for resolving references. One is to do it manuall...
Comparing two dataframes and getting the differences
... behaviour for pd.concat(), here's the docs pandas.pydata.org/pandas-docs/stable/merging.html
– Thanos
Apr 17 '16 at 18:35
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How do you do a limit query in JPQL or HQL?
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// SQL: SELECT * FROM table LIMIT start, maxRows;
Query q = session.createQuery("FROM table");
q.setFirstResult(start);
q.setMaxResults(maxRows);
share
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How to hide “Showing 1 of N Entries” with the dataTables.js library
How do you remove the "Showing 1 of N entries" line of text on a dataTable (that is when using the javascript library dataTables? I think I was looking for something along these lines...
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iOS 7 status bar back to iOS 6 default style in iPhone app?
...ontroller and UITabBarController will also try to pad the contentInsets of table views and collection views in its subview hierarchy. It does this in a manner similar to the status bar logic from #4. There is a programmatic way of preventing this, by setting automaticallyAdjustsScrollViewInsets to N...
H2 in-memory database. Table not found
I've got a H2 database with URL "jdbc:h2:test" . I create a table using CREATE TABLE PERSON (ID INT PRIMARY KEY, FIRSTNAME VARCHAR(64), LASTNAME VARCHAR(64)); . I then select everything from this (empty) table using SELECT * FROM PERSON . So far, so good.
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How do you query for “is not null” in Mongo?
...ta set like my sample) that rather than using an index, MongoDB will use a table scan, even for a potential covered index query. As it turns out that gives me an easy way to illustrate the difference here:
db.foo.find({}, {_id : 0, imageUrl : 1})
{ "imageUrl" : "http://example.com/foo.jpg" }
{ "im...
MySQL: selecting rows where a column is null
...for a certain column, it returns an empty set. However, when I look at the table in phpMyAdmin, it says null for most of the rows.
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Difference between shared objects (.so), static libraries (.a), and DLL's (.so)?
...c library(.a) is a library that can be linked directly into the final executable produced by the linker,it is contained in it and there is no need to have the library into the system where the executable will be deployed.
A shared library(.so) is a library that is linked but not embedded in the fin...
java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...tes you need to update characher-set and collation for utf8mb4:
database table/column:
alter table <some_table> convert to character set utf8mb4 collate utf8mb4_unicode_ci
database server connection (see)
On my development enviromnt for #2 I prefer to set parameters on command line when st...