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The following commands can be used to swap the names of two MySQL databases (<db1> and <db2>): mysqladmin -uroot -p<password> create swaptemp mysqldump -uroot -p<password> --routines <db1> | mysql -uroot -p<password> swaptemp mysqladmin -uroot -p<password&gt...

Renaming a table can be done in a single command: RENAME TABLE `<old name>` TO `<new name>`; The following syntax does exactly the same: ALTER TABLE `<old name>` RENAME TO `<new name>`; If renaming a temporary table, the ALTER TABLE version of the syntax must be used....

Renaming a column can be done in a single statement but as well as the new name, the "column definition" (i.e. its data type and other optional properties such as nullability, auto incrementing etc.) must also be specified. ALTER TABLE `<table name>` CHANGE `<old name>` `<n...

MERGE INTO targetTable t USING sourceTable s ON t.PKID = s.PKID WHEN MATCHED AND NOT EXISTS ( SELECT s.ColumnA, s.ColumnB, s.ColumnC INTERSECT SELECT t.ColumnA, t.ColumnB, s.ColumnC ) THEN UPDATE SET t.Colum...

$ printf '%(%F)T\n' 2016-08-17

$ printf -v now '%(%T)T' $ echo "$now" 12:42:47

Lets create a simple transformation to convert a CSV into an XML file. Our Transformation has to do the following: Read the CSV file Build the greetings message Save the greetings in the XML file Create a Transformation: Here's how to start the Transformation: To the left of the works...

Pentaho Data Integration comes in two varieties: Community Edition (CE) - Free version for developers Enterprise Edition (EE) - Paid version for enterprise use Installation steps: You can download Pentaho Data Integration Community Edition from Sourceforge.net. For the Enterprise Editio...

Sometimes when working with linear regression we need to check for non-linearity in the data. One way to do this is to fit a polynomial model and check whether it fits the data better than a linear model. There are other reasons, such as theoretical, that indicate to fit a quadratic or higher order ...

This example demonstrates how pointers can be used for C-like access to C# arrays. unsafe { var buffer = new int[1024]; fixed (int* p = &buffer[0]) { for (var i = 0; i < buffer.Length; i++) { *(p + i) = i; } } } The unsafe keyw...

Addition and subtraction in pointers works differently from integers. When a pointer is incremented or decremented, the address it points to is increased or decreased by the size of the referent type. For example, the type int (alias for System.Int32) has a size of 4. If an int can be stored in add...

In C and C++, the asterisk in the declaration of a pointer variable is part of the expression being declared. In C#, the asterisk in the declaration is part of the type. In C, C++ and C#, the following snippet declares an int pointer: int* a; In C and C++, the following snippet declares an int ...

C# inherits from C and C++ the usage of the symbol -> as a means of accessing the members of an instance through a typed pointer. Consider the following struct: struct Vector2 { public int X; public int Y; } This is an example of the usage of -> to access its members: Vector2...

So, you have completed installation it's time now to Run you program with it. Netbeans has created a shortcut to your desktop, "Double click" that to open the IDE. To Create a new project 1. Click this button OR Goto: files >> New Project then this window will popup Select...

Digital hardware is built from two types of hardware primitives: Combinatorial gates (inverters, and, or, xor, 1-bit full adders, 1-bit multiplexers...) These logic gates perform a simple boolean computation on their inputs and produce an output. Each time one of their inputs changes, they st...

Implementation of IDatabaseInitializer that is used in EntityFramework by default. As the name implies, it creates the database if none exists. However when you change the model, it throws an exception. Usage: public class MyContext : DbContext { public MyContext() { Database.SetIni...

This implementation of IDatabaseInitializer drops and recreates the database if the model changes automatically. Usage: public class MyContext : DbContext { public MyContext() { Database.SetInitializer(new DropCreateDatabaseIfModelChanges<MyContext>()); } }

This implementation of IDatabaseInitializer drops and recreates the database everytime your context is used in applications app domain. Beware of the data loss due to the fact, that the database is recreated. Usage: public class MyContext : DbContext { public MyContext() { Database.S...

You can create your own implementation of IDatabaseInitializer. Example implementation of an initializer, that will migrate the database to 0 and then migrate all the way to the newest migration (usefull e.g. when running integration tests). In order to do that you would need a DbMigrationsConfigur...

An implementation of IDatabaseInitializer that will use Code First Migrations to update the database to the latest version. To use this initializer you have to use DbMigrationsConfiguration type too. Usage: public class MyContext : DbContext { public MyContext() { Database.SetInitial...