ERROR: could not determine which collation to use for string comparison

Products

• VMware Tanzu Greenplum
• VMware Tanzu Greenplum / Gemfire
• VMware Tanzu Data Suite

Issue/Introduction

+ Error appears to occur on static columns if a UNION is used.

+ If a CAST is added, it is successful.

Example:

Error: 'a static value' as Col_Name

Success: Cast('a static value' as varchar) as Col_Name

Environment

Greenplum Database.

Resolution

This is a known PSQL error when the query that is running is within an SSIS package and not located on the master database server.

Using explicit type casting in the query will resolve the issue.