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Constraints in SQL

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Hello. In this tutorial, we will learn different constraints in SQL and will use the postgresql database running on Docker. 1. Introduction SQL stands for Structured Query Language and is used to extract and organize data stored in relational databases like MySQL, PostgreSQL, Oracle, etc. A relational database consists of rows and columns that allow fetching specific information from databases ...

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Where, Group by, Having, and Order by clause in SQL

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Hello. In this tutorial, we will learn WHERE, GROUP BY, HAVING, and ORDER BY clauses in SQL and will use the postgresql database running on Docker. 1. Introduction SQL stands for Structured Query Language and is used to extract and organize data stored in relational databases like MySQL, PostgreSQL, Oracle, etc. A relational database consists of rows and columns that ...

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SQL Case Statement

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Hello. In this tutorial, we will learn the SQL Case statements and will use the postgresql database running on Docker. 1. Introduction SQL stands for Structured Query Language and is used to extract and organize data stored in relational databases like MySQL, PostgreSQL, Oracle, etc. Also, a relational database consists of rows and columns that allow fetching specific information from databases ...

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SQL Like Statement vs iLike

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Hello. In this tutorial, we will learn about the SQL like statement vs the ilike and we will use the PostgreSQL database running on Docker. 1. Introduction SQL stands for Structured Query Language and is used to extract and organize data stored in relational databases like MySQL, PostgreSQL, Oracle, etc. A relational database consists of rows and columns that allow ...

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SQL Subquery

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Hello. In this tutorial, we will learn subqueries in sql and will use the postgresql database. 1. Introduction SQL stands for Structured Query Language and is used to extract and organize data stored in relational databases like MySQL, PostgreSQL, Oracle, etc. A relational database consists of rows and columns that allow fetching specific information from databases that can be used ...

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Patch request – Spring boot

Hello. In this tutorial, we will create a simple restful spring boot application and understand the implementation of the patch endpoint request. 1. Introduction PATCH is used when we want to apply the partial update to the resource and does not want to update the entire resource. @PatchMapping annotation is used in spring for mapping the HTTP PATCH requests onto ...

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Spring qualifier annotation

Hello. In this tutorial, we will create a simple hello world spring boot application and understand the usage of Qualifier annotation. 1. Introduction @Qualifer annotation in spring is used to identify beans of the same type. It is also used to annotate the custom annotations that behave as qualifiers. 2. Spring boot qualifier annotation Let us dive into some practice ...

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Guice – Google

1. Introduction Guice is a framework that makes it easier for your application to use the dependency injection (DI) pattern. Dependency injection is a design pattern wherein classes declare their dependencies as arguments instead of creating those dependencies directly. For example, a class ‘A’ needs class ‘B’ to perform its job, so class ‘A’ does not need to worry about ...

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Morphia – Java ODM for MongoDB

1. Introduction This is an in-depth article on Morphia Java ODM for MongoDB example. Mongo Database is a no SQL database. It has capabilities such as query language to retrieve from the database. It also provides operational and administrative procedures. Morphia can be used as Object Document Mapper for MongoDB. This operates on top of Java Driver for MongoDB. 2. ...

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Javalin REST API

1. Introduction This is an in-depth article related to the Javalin REST API. Javalin is a web framework used by Java and Kotlin developers. The framework runs on Jetty Web server. It is similar to koa.js. 2. Javalin 2.1 Prerequisites Java 7 or 8 is required on the linux, windows or mac operating system. Maven 3.6.1 is required for building ...

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