Redshift

Redshift Explain Command and Examples

Redshift Explain plan Command is used to get information or cost on individual operations required to execute given query. This command provides information on join operations, aggregate functions, etc. It provides information on how your query would be executed on Redshift under current condition. In this article, we will very how Redshift explain command works with an example. Page Content Introduction to Redshift Amazon Redshift Explain Command Redshift Explain Command Syntax Redshift Explain Command Example Redshift Explain Output Operators Benefits of Redshift explain plan Command Conclusion Introduction to Redshift Amazon…

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August 23, 2019
Redshift

Redshift CASE Statement, Usage and Examples

In general, the CASE expression or command is a conditional expression, similar to if-then-else statements found in other languages. CASE is used to specify a result when there are multiple conditions. In this article, we will check how to use Redshift CASE Statement, its syntax and usage with some examples. Post Content Introduction to Redshift CASE Statement Syntax and Examples of CASE Statements in Redshift Simple CASE Statements Searched CASE Statements Usage of CASE Statements in Redshift CASE Statements with Aggregation Redshift CASE Statement with Windows Functions Redshift CASE Statement…

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August 22, 2019
Redshift

Redshift Dynamic SQL Queries and Examples

When you are working on the various data sources and different kind of SQL queries, there may be situations where you want to generate dynamic SQL queries dynamically based on your requirement. In Redshift you can PREPARE SQL statement and EXECUTE it. Redshift also support use of EXECUTE command in Redshift stored procedures. In this article, we will check Redshift Dynamic SQL Queries, how to PREPARE them and run using EXECUTE statements. The dynamic SQL in Redshift can be useful in many scenarios, such as when you need to execute…

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August 19, 2019
Redshift

Working with Amazon Redshift Stored Procedure

Amazon Redshift supports stored procedures written in PL/pgSQL, a dialect of the PostgreSQL database language. Stored procedures in Redshift are used to encapsulate logic on the database side and can be executed by multiple client applications, improving code reusability and reducing the amount of duplicated code in your applications. In this article, we will check how to create a stored procedure in Redshift using simple examples. Amazon Redshift Stored Procedure Overview Amazon Redshift stored procedures are used to encapsulate the data migration, data validation and business specific logic's and same time…

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August 18, 2019
Apache Spark

How to Export Spark-SQL Results to CSV?

Data plays important role in today's decision making process. Be it online bookstore, e-commerce website or online food delivery applications use user data to provide better customer service. These are many organizations that share data to decision making systems. These companies provide data in the form of flat files or direct access to the source system. Many companies use Spark as an execution engine. In this article, we will check how to export Spark-SQL results to CSV flat file. The created flat files or CSV files then be transported using…

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August 16, 2019
General

Amazon Released PartiQL – An Open Source SQL Compatible Query language

Today, most of the business critical decisions are driven by data. As data grows, it is typically spread across a combination of relational databases, non-relational data stores, and data lakes. As per Harvard business review, on average, less than half of structured data is being used to make business critical decision. Structured data could be a data from relational databases. They do no have facilities to consider other data sources such as the local file system or NoSQL database data or data lakes. In this article, we will check newly…

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August 7, 2019
General

Best SQL Query Format Tools Online

Who does not like formatted SQL codes? They are easy to read, understand and follow the complex logic. Sometimes, when you export SQL code from the database, the code will become messy and hard to understand. In this article, we will check Best SQL query format tools available for free on the internet. Some of them provide an API so that you can integrate in your application. Best SQL Query Format Tools Before jumping on the tools introduction. let us understand why the SQL code formatting is important? Why do…

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July 22, 2019
Vertica

Vertica Derived Table and Examples

In a data warehouse environment, there are many places where you need to derive tables to meet certain requirements such as calculating columns, renaming table columns etc. You can use derived tables in place of temporary tables. In this article, we will check Vertica derived tables and how to use them in SQL queries. Vertica Derived Table A derived table in Vertica is basically a sub-query which is always in the FROM clause of a SQL query Statements. The reason it is called a derived table is because it essentially functions as a table as…

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June 24, 2019
Vertica

Vertica Cumulative Sum, Average and Example

The cumulative sum or running total is one of the interesting problem. Most of the modern analytical database line Netezza, Teradata, Oracle, Vertica provides supports to analytical functions. You can make use of those analytical functions along with window specification to calculate cumulative sum and average. In this article, we will check how to calculate Vertica Cumulative Sum (running total) or cumulative average. Vertica Cumulative Sum As explained earlier, cumulative sum or a running total is the summation of a sequence of numbers which is updated each time a new…

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May 3, 2019
Vertica

Vertica Set Operators: UNION, EXCEPT/MINUS and INTERSECT

The Vertica set operators are used to combine similar data sets from two or more SELECT statements. Here the similar data set literally means, the data type of the result set should also match, otherwise you have to explicitly use type conversion function for data columns when using set operators. The set operators in SQL are extensively used to combine results from various query sets. Based on your requirement, you can choose suitable Vertica set operators. Related Articles: Vertica WITH Clause, Syntax, Usage and ExamplesVertica Type Conversion Functions and Examples…

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April 25, 2019