Convert SQL DEFAULT Values to Sequelize defaultValue

DEFAULT Values in Sequelize

SQL columns can have default values that are applied when no explicit value is provided during INSERT. Sequelize maps these to the defaultValue option on field definitions.

Constant Defaults

String and numeric constants are converted directly:

status VARCHAR(20) DEFAULT 'active'
-- becomes -->
status: { type: DataTypes.STRING(20), defaultValue: 'active' }

retry_count INTEGER DEFAULT 3
-- becomes -->
retry_count: { type: DataTypes.INTEGER, defaultValue: 3 }

Boolean Defaults

The converter normalizes various boolean representations:

is_active BOOLEAN DEFAULT TRUE       --> defaultValue: true
is_deleted BOOLEAN DEFAULT FALSE     --> defaultValue: false
is_verified BOOLEAN DEFAULT 1        --> defaultValue: true

Timestamp Defaults

SQL timestamp functions are mapped to Sequelize constants:

SQL Default	Sequelize Default
CURRENT_TIMESTAMP	DataTypes.NOW
NOW()	DataTypes.NOW
CURRENT_TIMESTAMP()	DataTypes.NOW

UUID Generation

UUID generation functions map to Sequelize's built-in UUID generators:

SQL Default	Sequelize Default
gen_random_uuid()	DataTypes.UUIDV4
uuid_generate_v4()	DataTypes.UUIDV4
UUID()	DataTypes.UUIDV4
NEWID() (SQL Server)	DataTypes.UUIDV4

Database Functions

For other database functions, the converter uses sequelize.literal():

score DECIMAL DEFAULT RANDOM()
-- becomes -->
score: { type: DataTypes.DECIMAL, defaultValue: sequelize.literal('RANDOM()') }

Sequelize Behavior

When defaultValue is set, Sequelize includes it in the JavaScript model instance immediately upon Model.build() — you don't need to save to the database first to see the default. However, database-level defaults (via sequelize.literal) are only resolved after the INSERT executes.