Important notes and limitations

Performing reads and writes on the same source table

Performing reading and writing on the same source table is supported in Gluesync for PostgreSQL as long as you don’t have auto-increment fields in your SQL table. Please refer to the specific chapter below for more information. This is to avoid possible PKs collisions: we strongly suggest using field tables or also known as staging tables to perform a safe sync.

Identity fields in tables [auto-increment primary keys]

Identity fields, also known as auto-increment primary keys, are supported by Gluesync while performing reads from the source table replicating the value to the NoSQL target database.

Limitations

There are currently certain limitations while performing writes on tables that have such behavior on its columns because a document created in the NoSQL database could have a non-incremental value on its doc-ID used by Gluesync to re-ensemble the proper table/column structure. To avoid key collision Gluesync NoSQL to SQL module will throw an exception if this behavior is found in your environment. We’re currently working on supporting such functionality with support for Identity fields on the upcoming releases leaving the default connector behavior as safe as possible and advising the user about possible key collisions [the user will be required to force a flag in the configuration file to enable that feature, otherwise an exception will be thrown]. SQL professionals usually adopt what is called “exchange tables/border tables” to safely support imports of external writes.