How use Lateral Column Alias in Redshift?

Redshift lateral column alias, also known as derived column, is created from previously computed columns in the same SELECT statement. These columns are virtual and not stored in the table; their values are recalculated each time they are used in a query. Many PostgreSQL databases, like Netezza, support lateral column aliases. Recently, Redshift has also started supporting this feature. In this post, let’s explore this new capability. Page Content Introduction Benefits of Using Lateral Column Alias in Redshift How Lateral Column Alias Works in Redshift (with Example) Lateral Column Alias…

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Redshift Pivot and Unpivot Functions: A Comprehensive Guide

Pivot and unpivot are common functions in relational databases for converting rows to columns and vice versa. These function are supported by many relational databases, including Amazon Redshift, which has recently added support for PIVOT and UNPIVOT functions. However, other methods such as CASE or DECODE can be used as alternatives for converting rows to columns or columns to rows. In this article, we will explore the Redshift pivot and unpivot table functions in detail for transforming your data. Post Content Introduction Redshift Pivot and Unpivot Functions Pivot Tables in…

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Change Redshift Table Distribution: A Guide with Examples

Selecting an appropriate distribution style is a crucial factor in enhancing the efficiency of the Redshift Database. The distribution style you choose can have a direct impact on your query's performance. Using an incorrect distribution style for a table may adversely affect your Redshift cluster due to increased workload. This article will demonstrate how to change the distribution style of a Redshift table, along with an illustrative example. Page Content Introduction Redshift Table Distribution Styles Why to Change Redshift Table Distribution style? How to Change Redshift Table Distribution Style Changing…

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How to Choose the Right Distribution Style in Redshift?

Amazon Redshift uses the Massively parallel processing (MPP) technique, Redshift optimally distributes data and query load across all nodes available in the cluster. In this article, we will check how to choose the Right distribution style in Redshift and the importance of right distribution key. Right Distribution Style in Redshift When choosing a distribution style, it's important to consider the size and structure of your data and the types of queries you'll be running. Following are a few best practices to keep in mind while choosing an Amazon Redshift Data…

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What are Amazon Redshift Distribution Styles? – Examples

Amazon Redshift is one of the popular cloud-based data warehousing solution offered by Amazon Web Services (AWS). Amazon Redshift is a cluster of nodes with separate disks, memory and CPU. One of the important features of Amazon Redshift is the ability to choose from different distribution styles to manage the distribution of data and computation across nodes in a cluster. In this article, we'll discuss the different Amazon Redshift distribution styles and the best practices for choosing the right Redshift distribution style for your needs. Amazon Redshift Key Distribution Styles…

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How to use Redshift NOT NULL Constraint? Its Syntax

In my other Redshift related article, we have discussed how to define a primary key, Unique key and Foreign key constraint in Amazon Redshift. In this article, we will check how to use Redshift NOT NULL constraint with its syntax and examples. Redshift NOT NULL Constraint Similar to most of the MPP databases such as Snowflake, the Amazon Redshift database allows you to define constraints. The Redshift database does not enforce constraints like primary key, foreign key and unique key. But, it does enforce the NOT NULL constraint. Constraints other…

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How to use Redshift Foreign key Constraint? Its Syntax

In my other Redshift related article, we have discussed how to define a primary key NOT NULL and Unique key constraints in AWS Redshift. In this article, we will check how to use Redshift FOREIGN KEY constraint with its syntax and examples. Redshift Foreign Key Constraint Amazon AWS Redshift is an analytical columnar cloud database. It is mainly used for analyzing your data to create a key KPI to make critical business decisions. The Redshift cloud database is based on PostgreSQL 8.x and many transactional database features such as table…

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How to use Redshift Unique Key Constraint? Its Syntax

In my other Redshift related article, we have discussed how to define a primary key, foreign key and NOT NULL constraint. In this article, we will check how to use Redshift UNIQUE KEY constraint with its syntax. Redshift Unique Key Constraint Amazon AWS Redshift is an analytical columnar database. Many transactional database features are not supported on Redshift. You can define a unique key, but Unique key is informational only; They are not enforced by Amazon Redshift. The Amazon data warehouse appliance supports referential integrity constraints such as Redshift primary…

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How to use Redshift Primary key Constraint? Its Syntax

Amazon Redshift is one of the earliest cloud data warehouses. It is based on the PostgreSQL. There are many features that are common in Redshift and PostgreSQL. Amazon Redshift provides many features to the user who wants to migrate to AWS Redshift. One of such features is primary key constraints. Basically, Redshift supports the referential integrity constraint such as primary key, foreign key, not null and unique key. You can create a primary key during table creation, that is, table DDL or you can use alter table command to add…

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Redshift WHERE Clause Multiple Columns Support

The relational databases such as Teradata and Oracle supports the multiple columns in WHERE clause. It is one of the main requirements when you are migrating from legacy databases such as Teradata to Amazon Redshift. In this article, we will check Redshift WHERE clause multiple columns support. What is a WHERE Clause? The WHERE clause contains conditions that either apply predicates to columns in tables or join multiple tables. Almost all modern databases allow you to join tables in WHERE clause. The WHERE clause specifies a condition that matches a subset of…

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