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Indexes are a data structure that contains pointers to the contents of a table arranged in a specific order, to help the database optimize queries. They are similar to the index of book, where the pages (rows of the table) are indexed by their page number. Several types of indexes exist, and can be...

value1 ** value2 pow(value1, value2[, value3]) value1.__pow__(value2[, value3]) value2.__rpow__(value1) operator.pow(value1, value2) operator.__pow__(value1, value2) math.pow(value1, value2) math.sqrt(value1) math.exp(value1) cmath.exp(value1) math.expm1(value1)

The CREATE TABLE statement is used create a new table in the database. A table definition consists of a list of columns, their types, and any integrity constraints. CREATE TABLE tableName( [ColumnName1] [datatype1] [, [ColumnName2] [datatype2] ...] ) ParameterDetailstableNameThe name of the ...

UNION keyword in SQL is used to combine to SELECT statement results with out any duplicate. In order to use UNION and combine results both SELECT statement should have same number of column with same data type in same order, but the length of column can be different. SELECT column_1 [, column_2 ]...

All searching algorithms on iterables containing n elements have O(n) complexity. Only specialized algorithms like bisect.bisect_left() can be faster with O(log(n)) complexity.

public static IEnumerable<TReturn> Query<TFirst, TSecond, TReturn>( this IDbConnection cnn, string sql, Func<TFirst, TSecond, TReturn> map, object param = null, IDbTransaction transaction = null, bool buffered = true, string splitOn = "Id", int? commandTimeout = null, C...

Visual Basic .NET is the official successor to Microsoft's original Visual Basic programming language. Visual Basic [.NET] appears to have similarities to Python with the lack of semicolons and brackets, but shares with C++ the basic structure of functions. Curly braces are absent in VB .NET, but ...

ParameterDetailsPARTITION BYThe field(s) that follows PARTITION BY is the one that the 'grouping' will be based on The OVER clause determines a windows or a subset of row within a query result set. A window function can be applied to set and compute a value for each row in the set. The OVER claus...

git rebase [-i | --interactive] [options] [--exec <cmd>] [--onto <newbase>] [<upstream>] [<branch>] git rebase [-i | --interactive] [options] [--exec <cmd>] [--onto <newbase>] --root [<branch>] git rebase --continue | --skip | --abort | --edit-todo ...

ALTER command in SQL is used to modify column/constraint in a table ALTER TABLE [table_name] ADD [column_name] [datatype]

The Dropbox API allows developers to build Dropbox functionality directly into their apps. The API allows access to features such as file uploading, downloading, sharing, searching, and restoration. The API can be used across platforms such as Windows, Mac, Linux, iOS, Android, or any other that ...

Editing R Docs on Stack Overflow See the documentation guidelines for general rules when creating documentation. A few features of R that immigrants from other language may find unusual Unlike other languages variables in R need not require type declaration. The same variable can be assi...

Rust is a systems programming language designed for safety, speed, and concurrency. Rust has numerous compile-time features and safety checks to avoid data races and common bugs, all with minimal to zero runtime overhead. Stable VersionRelease Date1.17.02017-04-271.16.02017-03-161.15.12017-02...

trap action sigspec... # Run "action" on a list of signals trap sigspec... # Omitting action resets traps for signals ParameterMeaning-pList currently installed traps-lList signal names and corresponding numbers The trap utility is a special shell built-in. It's defined in POSI...

In C, some expressions yield undefined behavior. The standard explicitly chooses to not define how a compiler should behave if it encounters such an expression. As a result, a compiler is free to do whatever it sees fit and may produce useful results, unexpected results, or even crash. Code that i...

Due to the flaws of rand(), many other default implementations have emerged over the years. Among those are: arc4random() (available on OS X and BSD) random() (available on Linux) drand48() (available on POSIX)

ls [OPTION]... [FILE]... OptionDescription-a, --allList all entries including ones that start with a dot-A, --almost-allList all entries excluding . and ..-cSort files by change time-d, --directoryList directory entries-h, --human-readableShow sizes in human readable format (i.e. K, M)-HSame...

Shell aliases are a simple way to create new commands or to wrap existing commands with code of your own. They somewhat overlap with shell functions, which are however more versatile and should therefore often be preferred. The alias will only be available in the shell where the alias command...