Amazon Redshift automatically takes backups of your data & stores them for a definite amount of retention time.Plus no extra cost is involved for additional security features. Costing is minimal ranging from just 0.25$ per hour with & can be scaled to 1000$ per terabyte per year which is actually less than the cost of traditional on-premise solutions.You can run complex queries against loads of data (in terabytes or petabytes) of structured data using very sophisticated query optimization & massively parallel query execution.Redshift gives you fast querying capability over structured data using familiar SQL based clients & BI Tools.It has the following features that make it pretty useful compared to other Amazon Data Warehouses like Amazon S3, RDS, or Amazon DynamoDB. Table of ContentsĪmazon Redshift is a fast, fully managed cloud data warehouse that makes it simple & cost-effective to analyze all of the data using standard SQL and the existing Business Intelligence (BI) tools. ![]() In this article, you will learn about the importance of the Amazon Redshift Unload command along with the syntax and some examples. It can be used to analyze data in BI tools.Īmazon Redshift Unload saves the query result in Apache Parquet format that is 2x faster and consumes 6x less storage. Amazon Redshift Unload helps users to save the result of query data into Amazon S3. There are several instances where Data Scientists or Data Analysts need to analyze a smaller chunk of a large dataset but not small enough. Second Example:- Unload Table to Encrypted Files.First Example:- Unload Table to a CSV File.Standard Redshift Unload Command Parameters.Hevo, A Simpler Alternative to Integrate your Data for Analysis.INFO: UNLOAD completed, 2 record(s) unloaded successfully. schema = public and table = my_tokenized_tables INFO: UNLOAD completed, 0 record(s) unloaded successfully. INFO: UNLOAD completed, 3 record(s) unloaded successfully. Stg=# call unload_pro( 's3://datalake/test/', 'sc3,public', NULL) I have less than 2048 tables, if you have more than that, just add few more select unions in the below portion. RAISE info ' Unloading of the DB is success !!!' ,db || ''' delimiter ''' || delimiter || ''' IGNOREHEADER 1 REMOVEQUOTES gzip' table_name || '/'' iam_role ''' ||iamrole || ''' delimiter ''' || delimiter || ''' MAXFILESIZE 300 MB PARALLEL ADDQUOTES HEADER GZIP' Ĭopy_query := 'copy ' ||list.table_schema table_name || '_'' iam_role ''' ||iamrole schema = % and table = %',starttime, list.table_schema, list. SQL:= 'select * from ' ||list.table_schema Relname :: text AS table_name FROM pg_class pcĪND relname != 'unload_history' AND trim(nspname :: text) IN ( ON ns.n <= regexp_count(b.comma_quote_table, ',') + 1 įOR list IN SELECT nspname :: text AS table_schema, SELECT trim(split_part(b.comma_quote_table, ',', ns.n)) AS tname ON ns.n <= regexp_count(b.comma_quote_schema, ',') + 1 SELECT trim(split_part(b.comma_quote_schema, ',', ns.n)) AS sname SELECT listagg(tbl_name, ',') within GROUP ( ORDER BY tbl_name)ĭROP TABLE IF EXISTS sp_tmp_quote_schema ĭROP TABLE IF EXISTS sp_tmp_token_schema ĮXECUTE 'INSERT INTO sp_tmp_quote_schema VALUES ('|| quote_literal(sc_name)|| ')' ĮXECUTE 'INSERT INTO sp_tmp_quote_table VALUES ('|| quote_literal(tbl_list)|| ')' IF table_list IS NULL THEN DROP TABLE IF EXISTS sp_tmp_tablelist ĬREATE temp TABLE sp_tmp_tablelist (tbl_name VARCHAR(100)) ![]() SELECT listagg(sc_list, ',') within GROUP ( ORDER BY sc_list) IF schema_list IS NULL THEN DROP TABLE IF EXISTS sp_tmp_schemalist ĬREATE temp TABLE sp_tmp_schemalist (sc_list VARCHAR(100)) ĪND nspname NOT LIKE 'pg_%' GROUP BY nspname IAM ROLE and the Delimiter is hardcoded here You can get these things as variable or hardcoded as per your convenient.Ĭreate a table for maintain the unload history:ĬREATE OR replace PROCEDURE unload_pro(s3_location VARCHAR(10000),
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