God Table

This smell arises when a table contains excessive number of attributes.

Excessive number of attributes tend to violate the principles of normalization which in turn introduce a variety of problems. Additionally, it impacts maintainability of the database.

Example

CREATE TABLE bet_matches( id TEXT PRIMARY KEY, tx0_index INTEGER, tx0_hash TEXT, tx0_address TEXT, tx1_index INTEGER, tx1_hash TEXT, tx1_address TEXT, tx0_bet_type INTEGER, tx1_bet_type INTEGER, feed_address TEXT, initial_value INTEGER, deadline INTEGER, target_value REAL, leverage INTEGER, forward_quantity INTEGER, backward_quantity INTEGER, tx0_block_index INTEGER, tx1_block_index INTEGER, block_index INTEGER, tx0_expiration INTEGER, tx1_expiration INTEGER, match_expire_index INTEGER, fee_fraction_int INTEGER, status TEXT, FOREIGN KEY (tx0_index, tx0_hash, tx0_block_index) REFERENCES transactions(tx_index, tx_hash, block_index), FOREIGN KEY (tx1_index, tx1_hash, tx1_block_index) REFERENCES transactions(tx_index, tx_hash, block_index));

Tools

The following set of tools detects this smell: DbDeo(for SQL)

Reference

Redgate, “119 SQL Code Smells,” 2017.