From 966054841ad5ed25b48632d4f9d0a46ad5aad715 Mon Sep 17 00:00:00 2001 From: Michael Jalkio Date: Thu, 17 Aug 2017 21:08:40 -0700 Subject: [PATCH] Add note warning about NULL merge keys --- embulk-output-redshift/README.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/embulk-output-redshift/README.md b/embulk-output-redshift/README.md index 13011f66..c5d0d414 100644 --- a/embulk-output-redshift/README.md +++ b/embulk-output-redshift/README.md @@ -98,7 +98,7 @@ Redshift output plugin for Embulk loads records to Redshift. * Transactional: Yes. * Resumable: No. * **merge**: - * Behavior: This mode writes rows to some intermediate tables first. If all those tasks run correctly, inserts new records from intermediate tables after updating records whose keys exist in intermediate tables. Namely, if merge keys of a record in the intermediate tables already exist in the target table, the target record is updated by the intermediate record, otherwise the intermediate record is inserted. If the target table doesn't exist, it is created automatically. + * Behavior: This mode writes rows to some intermediate tables first. If all those tasks run correctly, inserts new records from intermediate tables after updating records whose keys exist in intermediate tables. Namely, if merge keys of a record in the intermediate tables already exist in the target table, the target record is updated by the intermediate record, otherwise the intermediate record is inserted. If the target table doesn't exist, it is created automatically. NOTE: Merge does not work correctly if merge keys contain `NULL`s. * Transactional: Yes. * Resumable: Yes.