Add troubleshooting guide for Redshift rETL

[joeynmq]

Proposed changes

The customer has encountered an error when initiating the first sync from their Redshift rETL source:

relation "tb_customers" does not exist

However, they were able to retrieve the records when testing in query builder. Here is the query they were using:

SELECT id id_do_cliente, email, document, name, telephone, date(created_at) cadastro_em 
FROM tb_customers

In the end, the issue was resolved by adding the schema name in front of the database table name:

SELECT id id_do_cliente, email, document, name, telephone, date(created_at) cadastro_em 
FROM <schema_name>.tb_customers

Supporting docs - Starting with Amazon Redshift Cluster for SQL Database Developer

If you don't use the schema name and execute the SELECT statement directly on "tables" table, you will get the execution exception:

Amazon Invalid operation: relation "tables" does not exist;

If you get such an error, be sure you are using the schema name in front of the database table name and check the schema name is correct.

Merge timing

ASAP once approved

[github-actions]

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