Tutorial by Topics: o

UNION DISTINCT -- dedups after combining the SELECTs UNION ALL -- non dedup (faster) UNION -- the default is DISTINCT SELECT ... UNION SELECT ... -- is OK, but ambiguous on ORDER BY ( SELECT ... ) UNION ( SELECT ... ) ORDER BY ... -- resolves the ambiguity UNION does not use multiple CP...

Examples to get you up and running quickly (and correctly) with ASP.NET WebAPI

Aggregations operations process data records and return computed results. Aggregation operations group values from multiple documents together, and can perform a variety of operations on the grouped data to return a single result. MongoDB provides three ways to perform aggregation: the aggregation p...

keybindings:: ::abbreviation:: Return KeybindingsDetails^Ctrl key!Alt key+Shift key#Windows key{enter}send enter key{tab}send tab key*wildcard, any key can be pressed down~key's native function will not be blocked<symbolspecifies left key (<+ is left shift)>symbolspecifies right k...

ParameterDetailsfuncpython function, which takes numpy arrays as its inputs and returns numpy arrays as its outputsinplist of Tensors (inputs)Toutlist of tensorflow data types for the outputs of func

:[<range>]g[lobal]/{<pattern>}/[<command>] :[<range>]g[lobal]!/{<pattern>}/[<command>] (inverted) :[<range>]v[global]/{<pattern>}/[<command>] (inverted) Vim's "global" command is used to apply an ex command to every line wher...

Session["Session_Key"] = Obj_Value; HTTP is stateless. ASP.NET session state is a framework that facilitates maintaining state between HTTP page requests. Session differs from the class level variables in its ability to remain available across post-backs and different pages. For ...

REST stands for Representational State Transfer (sometimes spelled "ReST"). It relies on a stateless, client-server, cacheable communications protocol and mostly HTTP protocol is used. It is primarily used to build Web services that are lightweight, maintainable, and scalable. A service ba...

Hadoop v1 commands: hadoop fs -<command> Hadoop v2 commands: hdfs dfs -<command>

The best complete wiki is available here in github.

To run the example, the command syntax is: bin/hadoop jar hadoop-*-examples.jar wordcount [-m <#maps>] [-r <#reducers>] <in-dir> <out-dir> To copy data into HDFS(from local): bin/hadoop dfs -mkdir <hdfs-dir> //not required in hadoop 0.17.2 and later bin/h...

Parallel collections facilitate parallel programming by hiding low-level parallelization details. This makes taking advantage of multi-core architectures easy. Examples of parallel collections include ParArray, ParVector, mutable.ParHashMap, immutable.ParHashMap, and ParRange. A full list can be f...

Dropwizard pulls together stable, mature libraries from the Java ecosystem into a simple, light-weight package that lets you focus on getting things done. Dropwizard has out-of-the-box support for sophisticated configuration, application metrics, logging, operational tools, and much more, allowin...

Categoricals are a pandas data type, which correspond to categorical variables in statistics: a variable, which can take on only a limited, and usually fixed, number of possible values (categories; levels in R). Examples are gender, social class, blood types, country affiliations, observation time...