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dblink EXTENSION is a technique to connect another database and make operation of this database so to do that you need: 1-Create a dblink extention: CREATE EXTENSION dblink; 2-Make your operation: For exemple Select some attribute from another table in another database: SELECT * FROM dblink...

FDW is an implimentation of dblink it is more helpful, so to use it: 1-Create an extention: CREATE EXTENSION postgres_fdw; 2-Create SERVER: CREATE SERVER name_srv FOREIGN DATA WRAPPER postgres_fdw OPTIONS (host 'hostname', dbname 'bd_name', port '5432'); 3-Create user mapping for postgres...

When you try to restore database from another server you might get the following error: Error 3154: The backup set holds a backup of a database other than the existing database. In that case you should use WITH REPLACE option to replace database with the database from backup: RESTORE DATABAS...

productFlavors { // Define separate dev and prod product flavors. dev { // dev utilizes minSDKVersion = 21 to allow the Android gradle plugin // to pre-dex each module and produce an APK that can be tested on // Android Lollipop without time c...

I have previously written documentation on this site in order to describe how to make web services on Symfony I will write again a tutorial for the symfony >= 3 version. We think that we have a installed web-server on a configured version of Symfony Framework. You must have composer (php packag...

Prerequisites JDK 1.7 or later installed. You can find the Oracle JDK's here. Steps Download Payara Server Full. Unzip the Payara Server at some location on your computer. We will use C:\payara41 as INSTALL_DIR for Windows users and /payara41 for Linux/Mac users. Starting / stopping Pa...

Let's understand something. JavaEE consists of a number of specifications. When you install an Application Server (Payara for example), you install all of the specifications at once. For example there's a specification for an ORM called JPA (Java Persistence API), a specification to build Component ...

Using the Profiler Class One very good practice is to use Profiler.BeginSample and Profiler.EndSample because it will have its own entry in the Profiler Window. Also, those tag will be stripped out on non-Development build using using ConditionalAttribute, so you don't need to remove them from you...

REPL stands for 'Read Evaluate Print Loop.' The REPL can be used to write and execute code one line at a time and is an alternative to writing code to a file and then compiling or interpreting the entire file before execution. To start the SMLNJ REPL from a command prompt: smluser> sml Standar...

The %>% operator can also be used to pipe the dplyr output into ggplot. This creates a unified exploratory data analysis (EDA) pipeline that is easily customizable. This method is faster than doing the aggregations internally in ggplot and has the added benefit of avoiding unnecessary intermediat...

All SML expressions return a value. The REPL stores the return value of the last evaluated expression. it provides the value of the last evaluated expression within the REPL. smluser> sml Standard ML of New Jersey v110.78 [built: Thu Jul 23 11:21:58 2015] - 3+4; val it = 7 : int - it; val i...

Assuming you have a handle on the Hibernate Session object, in this case named session: List<Object[]> result = session.createNativeQuery("SELECT * FROM some_table").list(); for (Object[] row : result) { for (Object col : row) { System.out.print(col); } } Thi...

The stack is a LIFO (last-in, first-out) data-structure, i.e. the most recent (or "last in") element added to the stack will be the first element removed ("first out"). Let us consider the example of books in a box. Only one book can be added or removed from from the box at a ti...

Operators that bound tighter (higher precedence) are listed first. OperatorsPrecedence group (≥3.0)PrecedenceAssociativity.∞left?, !, ++, --, [], (), {}(postfix)!, ~, +, -, ++, --(prefix)~> (swift ≤2.3)255left<<, >>BitwiseShiftPrecedence160none*, /, %, &, &*MultiplicationPrec...

You could migrate from team foundation version control to git by using an open source tool called Git-TF. Migration will also transfer your existing history by converting tfs checkins to git commits. To put your solution into Git by using Git-TF follow these steps: Download Git-TF You can downloa...

Swarm Mode Node Availability: Active means that the scheduler can assign tasks to a node. Pause means the scheduler doesn’t assign new tasks to the node, but existing tasks remain running. Drain means the scheduler doesn’t assign new tasks to the node. The scheduler shuts down any existing ta...

Worker Node: #Run the following on the worker node to leave the swarm. docker swarm leave Node left the swarm. If the node has the Manager role, you will get a warning about maintaining the quorum of Managers. You can use --force to leave on the manager node: #Manager Node docker swarm l...

(The following is a simplified version of what the Java Language Specification says. For a deeper understanding, you need to read the specification itself.) Happens-before relationships are the part of the Memory Model that allow us to understand and reason about memory visibility. As the JLS say...

The matplotlib.animation package offer some classes for creating animations. FuncAnimation creates animations by repeatedly calling a function. Here we use a function animate() that changes the coordinates of a point on the graph of a sine function. import numpy as np import matplotlib.pyplot as p...

The best way to get started using Spring-Integration in your project is with a dependency management system, like gradle. dependencies { compile 'org.springframework.integration:spring-integration-core:4.3.5.RELEASE' } Below is a very simple example using the gateway, service-activator mes...