Plan

The plan command generates a migration plan to apply a desired schema state to a target database schema. It compares the desired state (from a file) with the current state of a specific schema and shows what changes would be applied.

Overview

The plan command follows infrastructure-as-code principles similar to Terraform:

Read the desired state from a SQL file (with include directive support)
Connect to the target database and analyze current state of the specified schema
Compare the two states
Generate a detailed migration plan with proper dependency ordering
Display the plan without making any changes

Basic Usage

# Generate plan to apply schema.sql to the target database
pgschema plan --host localhost --db myapp --user postgres --password mypassword --file schema.sql

# Plan with specific schema
pgschema plan --host localhost --db myapp --user postgres --password mypassword --schema myschema --file schema.sql

# Generate JSON output for automation
pgschema plan --host localhost --db myapp --user postgres --password mypassword --file schema.sql --output-json stdout

# Generate SQL migration script
pgschema plan --host localhost --db myapp --user postgres --password mypassword --file schema.sql --output-sql stdout

# Save multiple output formats simultaneously
pgschema plan --host localhost --db myapp --user postgres --password mypassword --file schema.sql \
  --output-human plan.txt --output-json plan.json --output-sql migration.sql

# Disable colored output (useful for scripts or CI/CD)
pgschema plan --host localhost --db myapp --user postgres --password mypassword --file schema.sql --no-color

Connection Options

--host

string

default:"localhost"

Database server host

--port

integer

default:"5432"

Database server port

--db

string

required

Database name

--user

string

required

Database user name

--password

string

Database password (can also use PGPASSWORD environment variable)You can provide the password in two ways:

PGPASSWORD=mypassword pgschema plan \
  --host localhost \
  --db myapp \
  --user postgres \
  --file schema.sql

--schema

string

default:"public"

Schema name to target for comparison

Plan Options

--file

string

required

Path to desired state SQL schema file

--output-human

string

Output human-readable format to stdout or file pathExamples:

--output-human stdout - Display to terminal
--output-human plan.txt - Save to file

--output-json

string

Output JSON format to stdout or file pathThis JSON format is the same format accepted by the apply command for executing migration plans.Examples:

--output-json stdout - Display to terminal
--output-json plan.json - Save to file

--output-sql

string

Output SQL format to stdout or file pathExamples:

--output-sql stdout - Display to terminal
--output-sql migration.sql - Save to file

--no-color

boolean

default:"false"

Disable colored output for human format when writing to stdoutThis is useful for:

Scripts and automation that need to parse output
CI/CD environments that don’t support color codes
Redirecting output to files where color codes are unwanted

Note: This flag only affects human format output to stdout. File output and JSON/SQL formats are never colored.

Examples

Default Human-Readable Output

pgschema plan --host localhost --db myapp --user postgres --file schema.sql

Plan: 2 to add, 1 to modify, 1 to drop.

Summary by type:
  tables: 2 to add, 1 to modify, 1 to drop
  indexes: 1 to add
  functions: 1 to add

Tables:
  + users
  + posts
  ~ products
    + discount_rate (column)
    - old_price (column)
  - legacy_data

Indexes:
  + idx_users_email

Functions:
  + update_timestamp()

Transaction: true

DDL to be executed:
--------------------------------------------------

CREATE TABLE IF NOT EXISTS users (
    id SERIAL PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    email VARCHAR(255) UNIQUE
);

CREATE TABLE IF NOT EXISTS posts (
    id SERIAL PRIMARY KEY,
    title TEXT NOT NULL,
    user_id INTEGER REFERENCES users(id)
);

CREATE INDEX idx_users_email ON users(email);

CREATE FUNCTION update_timestamp() RETURNS TRIGGER AS $$
BEGIN
    NEW.updated_at = NOW();
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

ALTER TABLE products ADD COLUMN discount_rate numeric(5,2);

ALTER TABLE products DROP COLUMN old_price;

DROP TABLE legacy_data;

JSON Output for Automation

pgschema plan \
  --host localhost \
  --db myapp \
  --user postgres \
  --file schema.sql \
  --output-json stdout

{
  "version": "1.0.0",
  "pgschema_version": "1.0.0", 
  "created_at": "2025-01-15T10:30:00Z",
  "source_fingerprint": {
    "hash": "abc123def456..."
  },
  "diffs": [
    {
      "sql": "CREATE TABLE IF NOT EXISTS users (\n    id SERIAL PRIMARY KEY,\n    name VARCHAR(255) NOT NULL,\n    email VARCHAR(255) UNIQUE\n);",
      "type": "table",
      "operation": "create",
      "path": "public.users",
      "source": {
        "schema": "public",
        "name": "users",
        "type": "BASE_TABLE",
        "columns": [
          {
            "name": "id",
            "position": 1,
            "data_type": "integer",
            "is_nullable": false,
            "default_value": "nextval('users_id_seq'::regclass)"
          },
          {
            "name": "name",
            "position": 2,
            "data_type": "character varying",
            "is_nullable": false,
            "character_maximum_length": 255
          }
        ],
        "constraints": {
          "users_pkey": {
            "schema": "public",
            "table": "users",
            "name": "users_pkey",
            "type": "PRIMARY_KEY",
            "columns": [
              {
                "name": "id",
                "position": 1
              }
            ]
          }
        }
      },
      "can_run_in_transaction": true
    }
  ]
}

SQL Migration Script

pgschema plan \
  --host localhost \
  --db myapp \
  --user postgres \
  --file schema.sql \
  --output-sql stdout

CREATE TABLE IF NOT EXISTS users (
    id SERIAL PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    email VARCHAR(255) UNIQUE
);

CREATE TABLE IF NOT EXISTS posts (
    id SERIAL PRIMARY KEY,
    title TEXT NOT NULL,
    user_id INTEGER REFERENCES users(id)
);

CREATE INDEX idx_users_email ON users(email);

CREATE FUNCTION update_timestamp() RETURNS TRIGGER AS $$
BEGIN
    NEW.updated_at = NOW();
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

ALTER TABLE products ADD COLUMN discount_rate numeric(5,2);

ALTER TABLE products DROP COLUMN old_price;

DROP TABLE legacy_data;

Plan for Specific Schema

pgschema plan \
  --host localhost \
  --db multi_tenant \
  --user postgres \
  --schema tenant1 \
  --file tenant_schema.sql

Use Cases

Pre-deployment Validation

# Check what changes will be applied before deployment
pgschema plan \
  --host prod-db \
  --db myapp \
  --user readonly \
  --file new_schema.sql

# If plan looks good, proceed with apply
pgschema apply \
  --host prod-db \
  --db myapp \
  --user deployer \
  --file new_schema.sql

CI/CD Integration

# GitHub Actions example
- name: Validate Schema Changes
  run: |
    pgschema plan \
      --host ${{ secrets.DB_HOST }} \
      --db ${{ secrets.DB_NAME }} \
      --user ${{ secrets.DB_USER }} \
      --file schema/proposed.sql \
      --output-json plan.json \
      --no-color
    
    # Check if there are destructive changes
    if jq -e '.summary.to_destroy > 0' plan.json; then
      echo "Warning: Destructive changes detected!"
      exit 1
    fi

Change Tracking

# Generate plan and save for audit
DATE=$(date +%Y%m%d_%H%M%S)
pgschema plan \
  --host localhost \
  --db myapp \
  --user postgres \
  --file schema.sql \
  --output-sql "migrations/plan_${DATE}.sql"

Multiple Output Formats

You can generate multiple output formats simultaneously:

# Save all formats for comprehensive documentation
pgschema plan \
  --host localhost \
  --db myapp \
  --user postgres \
  --file schema.sql \
  --output-human plan.txt \
  --output-json plan.json \
  --output-sql migration.sql

# Display human-readable format and save JSON for automation
pgschema plan \
  --host localhost \
  --db myapp \
  --user postgres \
  --file schema.sql \
  --output-human stdout \
  --output-json automation/plan.json \
  --no-color

Note: Only one output format can use stdout. If no output flags are specified, the command defaults to human-readable output to stdout with colors enabled.

Comparison Direction

The plan command is unidirectional: it always plans changes from the current state (database) to the desired state (file).

Current State (Database) → Desired State (File)

This ensures:

Consistent infrastructure-as-code workflow
Clear source of truth (the file)
Predictable change direction

Include Directive Support

The plan command supports include directives in schema files, allowing you to organize your schema across multiple files:

-- main.sql
\i tables/users.sql
\i tables/posts.sql
\i functions/triggers.sql

The include processor will resolve all includes relative to the directory containing the main schema file.

Getting started

Workflow

CLI Reference

Overview

Basic Usage

Connection Options

Plan Options

Examples

Default Human-Readable Output

JSON Output for Automation

SQL Migration Script

Plan for Specific Schema

Use Cases

Pre-deployment Validation

CI/CD Integration

Change Tracking

Multiple Output Formats

Comparison Direction

Include Directive Support

Getting started

Workflow

CLI Reference

​Overview

​Basic Usage

​Connection Options

​Plan Options

​Examples

​Default Human-Readable Output

​JSON Output for Automation

​SQL Migration Script

​Plan for Specific Schema

​Use Cases

​Pre-deployment Validation

​CI/CD Integration

​Change Tracking

​Multiple Output Formats

​Comparison Direction

​Include Directive Support

Overview

Basic Usage

Connection Options

Plan Options

Examples

Default Human-Readable Output

JSON Output for Automation

SQL Migration Script

Plan for Specific Schema

Use Cases

Pre-deployment Validation

CI/CD Integration

Change Tracking

Multiple Output Formats

Comparison Direction

Include Directive Support