Chat with Postgresql Database

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  "name": "Chat with Postgresql Database",
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        "agent": "openAiFunctionsAgent",
        "options": {
          "systemMessage": "You are DB assistant. You need to run queries in DB aligned with user requests.

Run custom SQL query to aggregate data and response to user. Make sure every table has schema prefix to it in sql query which you can get from `Get DB Schema and Tables List` tool.

Fetch all data to analyse it for response if needed.

## Tools

- Execute SQL query - Executes any sql query generated by AI
- Get DB Schema and Tables List - Lists all the tables in database with its schema name
- Get Table Definition - Gets the table definition from db using table name and schema name"
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          "value": "gpt-4o-mini"
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      "credentials": {
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      "name": "Get Table Definition",
      "type": "n8n-nodes-base.postgresTool",
      "position": [
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      "parameters": {
        "query": "select
  c.column_name,
  c.data_type,
  c.is_nullable,
  c.column_default,
  tc.constraint_type,
  ccu.table_name AS referenced_table,
  ccu.column_name AS referenced_column
from
  information_schema.columns c
LEFT join
  information_schema.key_column_usage kcu
  ON c.table_name = kcu.table_name
  AND c.column_name = kcu.column_name
LEFT join
  information_schema.table_constraints tc
  ON kcu.constraint_name = tc.constraint_name
  AND tc.constraint_type = 'FOREIGN KEY'
LEFT join
  information_schema.constraint_column_usage ccu
  ON tc.constraint_name = ccu.constraint_name
where
  c.table_name = '{{ $fromAI(\"table_name\") }}'
  AND c.table_schema = '{{ $fromAI(\"schema_name\") }}'
order by
  c.ordinal_position",
        "options": {},
        "operation": "executeQuery",
        "descriptionType": "manual",
        "toolDescription": "Get table definition to find all columns and types"
      },
      "credentials": {
        "postgres": {
          "id": "nGI61D0TEEZz18rr",
          "name": "Your Postgresql Database Credentials"
        }
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      "typeVersion": 2.5
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        "content": "### 👨‍🎤 Setup
1. Add your **postgresql** and **OpenAI** credentials.
2. Click **Chat** button and start asking questions to your database.
3. Activate the workflow and you can make the chat publicly available."
      },
      "typeVersion": 1
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      "name": "Chat History",
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      "parameters": {
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        "content": "🛠️ Tools Used:
1. Execute SQL Query: Used to execute any query generated by the agent.
2. Get DB Schema and Tables List: It returns the list of all the tables with its schema name.
3. Get Table Definition: It returns table details like column names, foreign keys and more of a particular table in a schema."
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        "content": "👆 You can exchange this with any other chat model of your choice."
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      "parameters": {
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        "content": "👆 You can change how many number of messages to keep using `Context Window Length` option. It's 5 by default."
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      "name": "Execute SQL Query",
      "type": "n8n-nodes-base.postgresTool",
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      "parameters": {
        "query": "{{ $fromAI(\"sql_query\", \"SQL Query\") }}",
        "options": {},
        "operation": "executeQuery",
        "descriptionType": "manual",
        "toolDescription": "Get all the data from Postgres, make sure you append the tables with correct schema. Every table is associated with some schema in the database."
      },
      "credentials": {
        "postgres": {
          "id": "nGI61D0TEEZz18rr",
          "name": "Your Postgresql Database Credentials"
        }
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      "typeVersion": 2.5
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    {
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      "name": "Get DB Schema and Tables List",
      "type": "n8n-nodes-base.postgresTool",
      "position": [
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      "parameters": {
        "query": "SELECT 
    table_schema,
    table_name
FROM information_schema.tables
WHERE table_type = 'BASE TABLE'
    AND table_schema NOT IN ('pg_catalog', 'information_schema')
ORDER BY table_schema, table_name;",
        "options": {},
        "operation": "executeQuery",
        "descriptionType": "manual",
        "toolDescription": "Get list of all tables with their schema in the database"
      },
      "credentials": {
        "postgres": {
          "id": "nGI61D0TEEZz18rr",
          "name": "Your Postgresql Database Credentials"
        }
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