pgModeler vs SchemaSpy

pgModeler is a locally installed PostgreSQL schema engineering tool for Linux, macOS, and Windows. It supports visual design, reverse engineering, schema comparison and synchronization, and command-line deployment automation. Its relationship engine can propagate foreign-key columns, constraints, and indexes when tables are linked, and it supports more than 30 PostgreSQL object types. Models can be exported as SQL, PNG, SVG, HTML data dictionaries, or directly to a PostgreSQL server. The command-line interface can export DDL, run diffs, validate models, and automate CI/CD deployments. Models use human-readable XML; Plus adds a Git-powered versioning workflow. The software runs on the user's machine without an account, cloud dependency, or required internet connection. The community software is GPL v3 and free forever. Plus provides pre-built binaries and professional workflow features. Its listed single-user, six-month plan is $59.90 per month, billed from $59.90/6 months. Documentation warns that connection passwords are stored in plain text in the settings directory.

SchemaSpy is a free, open-source command-line application that reads database metadata and creates shareable HTML documentation. It generates entity-relationship diagrams from an existing database, collects structural statistics, and can export those statistics to Excel or CSV. Reports can identify design anomalies such as missing indexes, implied relationships, and orphan tables. The project says it supports over a dozen databases directly and can work with others through JDBC drivers. Documentation generation can be placed in a CI/CD workflow, and SchemaSpy can run against an empty database replica because it reads structural information. There is no graphical interface: distribution is through a JAR file or Docker image. Installation requires Java, a database JDBC driver, and viz.js or Graphviz for relationship diagrams. The JAR excludes drivers, while the Docker image includes drivers for MySQL, MariaDB, PostgreSQL, and jTDS for MSSQL. The listed plan price is free.