Frankkim/update tap to store nested data as jsonb field

[francisace]

PR Description for target-postgres

Title

Disable Table De-Nesting and Store All Nested JSON Objects in JSONB Columns

Description

Summary

This Pull Request addresses the handling of nested JSON objects in target-postgres. Instead of de-nesting the tables, all nested structures—including arrays—will now be stored directly in JSONB columns.

Motivation

Handling nested objects by creating separate tables (de-nesting) can result in a complex schema that's hard to manage and query. By storing the nested objects directly as JSONB, we simplify the schema and make it easier to query nested data.

Changes

• Disabled the table de-nesting logic.
• All nested JSON objects and arrays are now saved in JSONB columns.
• Updated the test cases to reflect these changes.

How it works

Here is an example to illustrate the new behavior:

Previous Behavior

For a JSON payload like the following:

{
  "name": "John",
  "info": {
    "email": "john@example.com",
    "address": {
      "city": "NY",
      "state": "NY"
    }
  }
}

The data would be saved in multiple tables, such as main_table, info_table, and address_table.

New Behavior
Now, the data will be saved in a single table with JSONB columns:

name	info
John	{"email": "john@example.com", "address": {"city": "NY", "state": "NY"}}