As an alternative you can use psql command line interface to unload table directly to the local system.įor more details, follow my other article, Export Redshift Table Data to Local CSV format. You cannot use unload command to export file to local, as of now it supports only Amazon S3 as a destination. Iam_role 'arn:aws:iam::123456789012:role/myRedshiftRole' Unload Redshift Table to Local System A few days ago, we needed to export the results of a Redshift query into a CSV file and then upload it to S3 so we can feed a third party API.
You should provide option HEADER to export results with header. Iam_role 'arn:aws:iam::123456789012:role/myRedshiftRole' Unload Redshift Query Results with Header However, It is recommended to set PARALLEL to TRUE.įor example, unload ('SELECT * from warehouse') Otherwise, the lshipdate column data isn't in the Parquet files. Do not include line breaks or spaces in your credentials-args string. unload ( 'select from lineitem' ) to 's3://mybucket/lineitem/' iamrole 'arn:aws:iam::0123456789012:role/MyRedshiftRole' PARQUET PARTITION BY (lshipdate) INCLUDE In these cases, the lshipdate column is also in the data in the Parquet files.
#REDSHIFT UNLOAD PARQUET PDF#
In order to unload results to a single file, you should set PARALLEL to FALSE. Database Developer Guide UNLOAD examples PDF RSS Unload VENUE to a pipe-delimited file (default delimiter) Note These examples contain line breaks for readability. Unload Redshift Query Results to a Single File
As unload command export the results in parallel, you may notice multiple files in the given location. The command will unload the warehouse table to mentioned Amazon S3 location. However, you can always use DELIMITER option to override default delimiter. You can query these columns using Redshift Spectrum or ingest them back to Amazon Redshift using the COPY command. The UNLOAD documentation does not show Parquet or Avro as output formats. I saw today, AWS has recently added the support to unload data by specifying the format. This enables semistructured data to be represented in Parquet. UNLOAD ('select-statement') TO 's3://object-path/name-prefix' FORMAT PARQUET. Amazon Redshift represents SUPER columns in Parquet as the JSON data type. ]įollowing is the example to unload warehouse table to S3. You can unload tables with SUPER data columns to Amazon S3 in the Parquet format. You can provide one or many options to unload command.
UNLOAD ('select-statement')įollowing are the options.
#REDSHIFT UNLOAD PARQUET DOWNLOAD#
You will have to use AWS CLI commands to download created file.įollowing is the unload command syntax. It does not unload data to a local system. Unload command unloads query results to Amazon S3.
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