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Summary

To maintain database integrity over time, we recommend that your Postgres table have an independent primary key - that is, your Postgres table should not take the primary key values from the opposing data source in the sync.

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How to set up your primary key

Each Postgres table you sync with Bracket should have a primary key constraint, and the primary key should have a default value that is unique. We recommend using UUIDv4 primary keys, which you can automatically generate using the command below in your CREATE TABLE SQL statement. 
CREATE TABLE IF NOT EXISTS public.my_table
    (pkey text COLLATE pg_catalog."default" NOT NULL DEFAULT uuid_generate_v4())
This ensures that all newly added records, whether inserted directly to Postgres or synced from a paired data source, will adopt primary keys with uniform formatting and unique values. In the field mapping, you are able to sync the primary key to a field in the opposing data source for reference, but any edits made to the primary key in the opposing source will not sync back to Postgres in the polling sync method.