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Author Archives: Mary Zheng

Mary has graduated from Mechanical Engineering department at ShangHai JiaoTong University. She also holds a Master degree in Computer Science from Webster University. During her studies she has been involved with a large number of projects ranging from programming and software engineering. She works as a senior Software Engineer in the telecommunications sector where she acts as a leader and works with others to design, implement, and monitor the software solution.

Date Format in SQL

In this article, we will explain the Date Format in SQL. 1. Introduction Structured Query Language (SQL) defines the date and time data types. In this example, I will use the MySQL database to demonstrate both date data types and corresponding utility functions. DATE – stores a calendar date in the YYYY-MM-DD format. The valid date ranges from ‘0000-01-01‘ to ...

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Introduction to SQL Basics

In this article, we will make an introduction to SQL Basics. 1. Introduction Structured Query Language (SQL) is a standardized database language that is used to create, maintain, and retrieve data from a relational database. SQL was initially developed at IBM San Jose Research Laboratory in early 1970. IBM released the first Relational Database Management System (RDBMS) – Multics_Relational_Data_Store in June ...

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SQL SELECT DISTINCT Statement

In this article, we will explain the SQL SELECT DISTINCT Statement. 1. Introduction The SQL DISTINCT keyword is used to eliminate the duplicate records and return only unique records. Here is the SELECT DISTINCT syntax: SELECT DISTINCT {column1}, {column2}, ... FROM {table_name} [WHERE {condition}] 2. Technologies Used The example code in this article was built and run using: MySQLDocker 3. ...

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MySQL UPDATE Statement

In this example, I will demonstrate how to use the UPDATE statement to modify values using MySQL. 1. Introduction MySQL is an open-source relational database management system. Here is the UPDATE statement syntax: UPDATE {table_name} SET {assignment_list} [WHERE where_condition] {table_name} – the table name.{assignment_list} – one or more assignments which update records.[WHERE where_condition] – optional condition. 2. Technologies Used The ...

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SQL UNION Operator

In this article, we will explain the SQL UNION Operator through examples. 1. Introduction SQL UNION operator combines results from two select statements into a single result which includes all unique rows. UNION ALL includes duplicated rows in the combined result. The syntax is as the following: SELECT_QUERY_1 UNION [ALL] SELECT_QUERY_2 Note, the two SELECT queries must meet the following ...

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Microservices Architecture Tutorial

1. Introduction Microservices architecture builds an application with many loosely coupled and independently deployable artifacts. In this example, I will demonstrate a simplified microservices architecture with two services. Figure 1 Simplified MSA The course service runs at port 9001.The student service runs at port 9002.The student service depends on the course service.The Eureka Server runs at port 8761. 2. Technologies ...

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How to Download and Install Java 16

In this article, we will explain how to Download and Install Java 16. 1. Introduction Oracle released JDK 16 on March 16, 2021. Let’s see how to download and install Java 16 (Oracle JDK 16). 2. Download Oracle JDK 16 In this step, I will download the installer from the Oracle website. First, open a web browser and navigate to ...

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SOA vs Microservices: What’s the Difference?

In this article, we will see a comparison between SOA vs Microservices and their basic differences. 1. Introduction A service is a single software unit that performs business tasks. Service-oriented architecture (SOA) is a software architecture where distinct components of an application provide services to other components via a communications protocol over the network. SOA composes a complex application by ...

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Microservices Tutorial for Beginners

This is a tutorial for beginners about Microservices. 1. Introduction Dr. Peter Rogers spoke about “micro web services” at a cloud computing conference in 2005. A workshop of software architects held near Venice in May 2011 used the term “microservice” to describe a common architectural style. IBM defines microservices as an architectural approach to deploying a single application with many ...

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Java 16 New Features Tutorial

1. Introduction Java 16 has a list of new features. In this tutorial, I will demonstrate the following new features: Java language – add a new java.lang.record type and the instanceof the method supports pattern matching.Java API – Stream API adds toList() and mapMulti() methods. 2. Technologies Used The example code in this article was built and run using: Java ...

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