.dbSchema

dataTypes
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string, number, boolean, map, array, null, timestamp, geopoint, reference (document path)

users (external - from Firebase - https://firebase.google.com/docs/reference/js/firebase.User)
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    displayName         string | null
    email               string | null
    emailVerified       boolean
    phoneNumber         string | null
    photoURL            string | null
    uid                 string
    

users (internal) ???
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    ext_user_id     string
    user_id         INT
    
  
expenses (https://plaid.com/docs/#transactions)
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    user_id                 string
    expense_id              string
    account_id              string
    category                [string] | null
    name                    string
    amount                  number
    iso_currency_code       string | null
    date                    timestamp
    location                geopoint | null
    pending                 boolean


income - TODO
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goals
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goal_id         string
image           string | null
name            string
description     string | null
price           number
time            timestamp | null?
priority        number (0-4)




categories_expenses
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category_id         string
name                string


budget - TODO
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budget_id
category_id
time
amount


categories_income - TODO
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