Redshift SELECT Distinct is used to fetch unique rows from the table. DISTINCT is applied to all the columns mentioned in the SELECT clause and not just the first column. The example fetches DISTINCT values for one column in the table catgroup Sports Shows Concerts redshift select distinct multiple columns You can apply DISTINCT on …
Redshift ORDER BY is used to sort the output rows in the result set. You can sort the output rows in ascending or descending order. By default, the sorting order is ascending. You can sort output rows on the basis of single column, multiple columns or even combination of ascending and descending for different columns. …
In SQL, ALIAS means another name given to objects like columns & tables. You can use column and table aliases to make sql query more readable and easier for developer too to write the query. In most of the cases, creating an alias is optional however in the cases where you are joining multiple tables …
In this post, I will show you how you can use SELECT statements in Redshift to query data from tables. SELECT is used to fetch one or more columns directly from the table. The SELECT is one of the most simple and yet challenging at times statement in Redshift. SELECT can become complex while creating …
Amazon Redshift supports loading columnar file formats like PARQUET, ORC. This extends compatibility and possibility of moving data easily from different environments for your data lake or data warehouse. Parquet primarily is a very popular file format on Hadoop and is first preference of Big Data experts. Now you can load parquet files in Amazon …
Should you use PARQUET files with Redshift Copy ? Read More »
In the previous post, we saw that you can create table in redshift by specifying 3 minimum details : Table Name, Column Name & Column Datatype. Redshift automatically adds encoding & distribution style to the table if nothing is specified explicitly. In this post, we will see 4 ways in which can create table in …
In the previous post, we created few tables in Redshift and in this post we will see how to load data present in S3 into these tables. To load data into Redshift, the most preferred method is COPY command and we will use same in this post. COPY command loads data in parallel leveraging the …
