Amazon Redshift Pad Zeros – LPAD and RPAD Examples

The Redshift pad functions are string functions used to remove or add the string at the beginning or at the end of the expression. An expression could be a column value from your Redshift database or schema table. In this article, we will check Redshift pad zeros using built in pad functions. Page Contents Introduction to Redshift String Functions Amazon Redshift LPAD and RPAD Functions Redshift LPAD Function Redshift RPAD Function Amazon Redshift LPAD and RPAD Examples Benefits of LPAD and RPAD functions in Redshift Conclusion Introduction to Redshift String…

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AWS Redshift Type of Subqueries with an Examples

A subquery in a database is a select expression that is enclosed in parentheses as a nested query block in a query statement. The Subquery may return zero to one or more values to its upper select or parent select statements. In this article, we will check Redshift type of subqueries with an examples. Redshift Subqueries Page Contents Introduction to Amazon Redshift Subqueries Redshift Type of Subqueries Best Practices for Redshift Subqueries Conclusion Introduction to Amazon Redshift Subqueries A subquery in Redshift is a nested select statement, that return zero…

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AWS Redshift Correlated Subquery and its Restrictions

Redshift Correlated subquery is a query within a query that refer the columns from the parent or outer query. This kind of subquery contains one or more correlations between its columns and the columns produced by the outer query. Redshift does support the regular and correlated subqueries. In most cases, the Redshift correlated subqueries are used to improve the SQL query performance. Page Contents Introduction to Redshift Correlated Subquery What is Redshift Correlated Subquery? Examples of Redshift Correlated Subquery Redshift Correlated Subquery Performance Considerations Redshift Correlated Subquery Restrictions Conclusion Introduction…

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Redshift Extract Function Usage and Examples

Redshift extract function extracts the sub field represented by units from the date/time value, interval, or duration specified for column. This function is equivalent to Redshift date_part() function. Page Contents Introduction to String Functions Amazon Redshift Extract Function Redshift Extract Function Datepart or Timepart and Abbreviations Amazon Redshift Extract Function Examples Benefits of Extract Function in Amazon Redshift Conclusion Introduction to String Functions The extract function is very useful when you are working with different heterogeneous data sources. You may have requirement to extract part of timestamp values and pass it to an…

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Redshift Interval Data Types and Conversion Examples

Amazon Redshift supports interval types in the same way as other postgreSQL databases such as Netezza, Vertica, Oracle, etc. It accepts interval syntax with unit specifications. You have to specify the units along withe interval value. In this article we will check Redshift interval data types and conversion Examples. Redshift Interval Data Types Use an interval literal to identify specific periods of time, such as 10 hours or 6 days. You can use these interval literals in conditions and calculations that involve date-time expressions. Redshift accepts the interval syntax, but…

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Optimize Query Performance with Redshift Collocated Tables

In a Redshift data warehouse appliance, if two tables use same distribution style and column, then rows for joining columns are on the same data slices. These types of tables are called collocated tables as required data is available in same data slice and less data needs to be moved during query execution. If you join two tables which uses same distribution style and column, then join is called collocated join. In this article, we will check how to optimize the query performance with Redshift collocated tables. How to Create…

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What are Redshift Sequence Alternative? – Example

In a database management system, sequence is a named object in an individual database, that can provide the unique value when get next value method. Usually, sequences are used to generate unique numbers that can be used as surrogate key value, for example, you can use that surrogate key as a primary key values. Redshift does not support sequences. But, however, there are alternative methods. In this article, we will check Redshift sequence alternative methods with some examples. Page Contents Introduction to Amazon Redshift What are Sequence in SQL? Benefits…

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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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Redshift Transaction Management – BEGIN, COMMIT, ROLLBACK

In a Redshift, transaction is a series of one or more operations on database objects and/or data. The transaction management is process of ensuring the transaction is successfully completed and committed in the Redshift database schema. In this article, we will discuss about the Amazon Redshift transaction management using BEGIN, COMMIT and ROLLBACK. We will check how transaction management works inside Redshift stored procedures. Page Content Introduction Redshift Transaction Management Redshift BEGIN Command Redshift BEGIN Syntax and Example Redshift COMMIT Command Redshift COMMIT Syntax and Example Redshift ROLLBACK Command Redshift…

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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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