jahe

-- Remove All Rows from a Table
TRUNCATE TABLE user;

-- Create a CHECK constraint to ensure consistency within the tables (e.g. for enumeration values or for consistency rules based on multiple columns)
-- Unnamed inline CHECK constraint
CREATE TABLE Persons (
  Age int CHECK (Age>=18)
);

-- Named inline CHECK constraint

jahe

// imports a couple of java tasks
apply plugin: "java"

// List available tasks in the shell
> gradle tasks

// A Closure that configures the sourceSets Task
// Sets the main folder as Source folder (where the compiler is looking up the .java files)
sourceSets {
  main.java.srcDir "src/main"

jahe

There is a MANIFEST.MF file in .jar files

It supports a wide range of functionality:
* electronic signing
* version control
* package sealing

It always sits in "META-INF/MANIFEST.MF"

The creation of a .jar file includes the creation of a default manifest file

jahe

// Move cursor to end of line (eol)
$

// Move cursor to the beginning of line
0

// Move cursor to the first character of the next word
w

// Move cursor to the last character of the word

jahe

// Open a file with the default App for this kind of filetype
open README.txt

jahe

-- Start Transaction update a row and rollback transaction
BEGIN TRANSACTION
UPDATE user SET username='peter' WHERE id=2
ROLLBACK TRANSACTION

-- Start Transaction update a row and commit transaction
BEGIN TRANSACTION
UPDATE user SET username='peter' WHERE id=2
COMMIT TRANSACTION

jahe

Java EE

Java EE consists of the following components

• JavaBeans
• JNDI - Java Naming and Directory Interface
• EJB
• Servlets
• JDBC
• JSP
• RMI
• RMI-IIOP

jahe

# Start MongoDB server
> mongod

# Start MongoDB CLI client
> mongodb

# Create or open database "myDatabase"
> use myDatabase

# Show a list of all databases

jahe

// VM Arguments vs. Program Arguments
// Program Arguments are accessible via the main() methods String[] args array
// VM Arguments are accessible via System.getProperty(<vm-arg-name>)
java [-D<vm-arg-name>=<vm-arg-value>] MyJavaProgram [<program-arg-value>]

// Activate Remote Debugging on JVM via Java Debug Wire Protocol (JDWP)
java -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=7777

// Listening for a debugger to connect: Yes or No
// No: JVM tries to connect to a debugger under the "address" field

jahe

// - DEBUGGER -
// Run to a specific line
Move cursor to the line -> Press "Ctrl + R"

// Terminate execution
Ctrl + F2

// Toggle Breakpoint
Ctrl + Shift + B