Snowdiff

A fast, pragmatic TUI tool to compare Snowflake table and view schemas using DDL files.
Quickly see what tables, views, and columns are missing or different between two environments.

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Features

• Compares two sets of Snowflake DDLs (source and target)
• Reports missing tables, views, and columns in either direction
• Shows a unified diff for each differing object (table/view)
• Handles Snowflake-specific quirks (e.g., TIMESTAMP_NTZ, unsupported DDLs)
• Works with DDLs generated by GET_DDL or SHOW CREATE
• Terminal UI for interactive navigation

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Usage

1. Prepare Your DDL Files

Export your source and target schema DDLs from Snowflake, for example:

-- For Target
SELECT GET_DDL('DATABASE', 'MYDB', TRUE);

-- For Source
SELECT GET_DDL('DATABASE', 'MYDB_DEV', TRUE);

Save the DDLs to two files, e.g.:

• ddls/source.sql
• ddls/target.sql

2. Build the Tool

cargo build --release

3. Run the Tool

By default, the tool loads ddls/source.sql and ddls/target.sql.
To run:

cargo run

4. TUI Navigation

• j / k or ↓ / ↑: Move up/down the diff list
• g / G or Home / End: Jump to top/bottom
• q or Esc: Quit

Selecting an object shows the unified diff for its DDL.

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How It Works

• Preprocesses DDL to handle Snowflake-specific types and remove unsupported statements
• Parses DDL into an AST using sqlparser-rs
• Normalizes database names for cross-environment comparison
• Diffs tables, views, and columns (including types)
• Displays a unified diff for each object in a TUI

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Limitations

• Only compares tables and views (not other object types)
• Requires DDLs to be exported from Snowflake
• No CLI arguments yet—edit the DDL file paths in src/main.rs if needed
• Does not connect directly to Snowflake
• DDL parsing is best-effort; some complex DDLs may not be fully supported

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Development

• Main logic in src/
• TUI in src/tui.rs
• DDL parsing in src/parser.rs
• Diff logic in src/differ.rs
• Types in src/types.rs

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License

MIT