![]() ![]() Instead, make sure that you apply the functions to the compared values so that the sort key is used. Keep in mind that SQL functions (such as data transformation functions) applied to sort key columns in queries reduce the effectiveness of the sort key for those queries. We also recommend using the sort key on columns often used in the WHERE clause of the report queries. If Amazon Redshift determines that applying a SORTKEY improves cluster performance, tables are automatically altered within hours from the time the cluster was created, with minimal impact to queries. This way, Amazon Redshift uses automatic table optimization to choose the sort key. We recommend creating your tables with SORTKEY AUTO. If the data isn’t sorted, more of the disk blocks (possibly all of them) have to be scanned, resulting in the query running longer. In this case, you can eliminate up to 98% of the disk blocks from the scan. Now suppose a query on the orders table specifies a date range of 1 month on the order_date column. A contrived example would be having an orders table with 5 years of data with a SORTKEY on the order_date column. Sorting enables efficient handling of range-restricted predicates to scan the minimal number of blocks on disk to satisfy a query. Sort keysĭefining a table with a sort key results in the physical ordering of data in the Amazon Redshift cluster nodes based on the sort type and the columns chosen in the key definition. MicroStrategy recommends following Amazon Redshift recommended best practices when implementing the physical schema of the base tables. MicroStrategy, like any SQL application, transparently takes advantage of the distribution style defined on base tables. You can use automatic table optimization to get started with Amazon Redshift easily or optimize production workloads while decreasing the administrative effort required to get the best possible performance. With AUTO distribution, Amazon Redshift assigns an optimal distribution style based on the size of the table data. If you don’t specify a distribution style, Amazon Redshift uses AUTO distribution. When you create a table, you can designate one of four distribution styles: AUTO, EVEN, KEY, or ALL. The goal in choosing a table distribution style is to minimize the impact of the redistribution step by locating the data where it needs to be before the query is run. When you run a query, the query optimizer redistributes the rows to the compute nodes as needed to perform any joins and aggregations. When you load data into a table, Amazon Redshift distributes the rows of the table to each of the compute nodes according to the table’s distribution style. Amazon Redshift has custom JDBC and ODBC drivers that you can download from the Connect Client tab on the Amazon Redshift console, allowing you to use a wide range of familiar BI tools.įor additional details about RA3 features, see Amazon Redshift RA3 instances with managed storage. Amazon Redshift delivers fast query performance by using columnar storage technology to improve I/O efficiency and parallelizing queries across multiple nodes. It provides a simple and cost-effective way to analyze all your data using your existing BI tools. ![]() Optimized for cloud and on-premises deployments, the platform features HyperIntelligence, a breakthrough technology that overlays actionable enterprise data on popular business applications to help users make smarter, faster decisions.”Īmazon Redshift is a fast, fully managed, petabyte-scale data warehouse. MicroStrategy provides modern analytics on an open, comprehensive enterprise platform used by many of the world’s most admired brands in the Fortune Global 500. Our vision is to enable Intelligence Everywhere. In their own words, “MicroStrategy is the largest independent publicly traded business intelligence (BI) company, with the leading enterprise analytics platform. This is a guest blog post co-written by Amit Nayak at Microstrategy. ![]()
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