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Fields API Reference

The github.com/forgego/forge/schema package provides constructor functions and options for defining typed model fields.

Field Types & Constructors​

Every field type can be constructed via fluent builder constructors or functional options:

Numeric Fields​

  • schema.Int64("id") / schema.Int64Field("id", ...): 64-bit integer (BIGINT).
  • schema.Int32("age") / schema.Int32Field("age", ...): 32-bit integer (INTEGER).
  • schema.Float64("score") / schema.Float64Field("score", ...): Double precision float.
  • schema.Float32("ratio") / schema.Float32Field("ratio", ...): Single precision float.
  • schema.Decimal("amount", 12, 2) / schema.DecimalField("amount", ...): Fixed-point decimal number.

Text & String Fields​

  • schema.String("name") / schema.StringField("name", ...): Variable length string with optional MaxLength.
  • schema.Text("body") / schema.TextField("body", ...): Unbounded long text (TEXT).
  • schema.Email("email") / schema.EmailField("email", ...): Email address with automatic format validation.
  • schema.URL("website") / schema.URLField("website", ...): Web URL with URL format validation.
  • schema.UUID("identifier") / schema.UUIDField("identifier", ...): Universally unique identifier.

Temporal Fields​

  • schema.Time("seen_at") / schema.TimeField("seen_at", ...): a point in time, the same timestamp column as DateTimeField.
  • schema.Date("day") / schema.DateField("day", ...): Calendar date without time.
  • schema.DateTime("timestamp") / schema.DateTimeField("timestamp", ...): Full timestamp with timezone.

Boolean & Binary Fields​

  • schema.Bool("is_active") / schema.BoolField("is_active", ...): Boolean flag (BOOLEAN or INTEGER 0/1).
  • schema.JSON("payload") / schema.JSONField("payload", ...): Structured JSON/JSONB document.
  • schema.Bytes("raw_data") / schema.BytesField("raw_data", ...): Binary payload (BYTEA / BLOB).

Field Configuration Options​

Database Layout & Constraints​

  • Primary(): Marks the field as the primary key.
  • AutoIncrement(): Enables database sequence / auto-increment.
  • Required(): Adds a NOT NULL constraint.
  • Unique(): Adds a UNIQUE constraint and index.
  • DBDefault(expr): Sets a database-level default SQL expression (e.g. DBDefault("NOW()") or DBDefault("'active'")).
  • DBColumn(name): Explicit SQL column name override.
  • DBType(sqlType): Explicit SQL column type override.
  • DBIndex(): Instructs migrations to create a B-Tree index.
  • DBCollation(name): Specifies character collation.
  • DBComment(text): Adds a database comment to the column.

Generated Columns​

  • GeneratedColumn(expression, isStored): Defines a computed database column. 
    // PostgreSQL STORED generated column
    schema.GeneratedColumn("price * (1 + tax_rate)", true)

Validation Options​

  • MaxLength(n int): Maximum string or array length.
  • MinLength(n int): Minimum string or array length.
  • MaxValue(v float64): Upper numerical bound.
  • MinValue(v float64): Lower numerical bound.
  • MaxDigits(n int) / DecimalPlaces(n int): Precision and scale for decimal numbers.
  • ChoicesOpts(choices ...Choice): Permitted enumerated choices.

Temporal Helpers​

  • AutoNowAdd(): Sets timestamp automatically on record creation (like created_at).
  • AutoNow(): Sets timestamp automatically on every record save (like updated_at).

UI & Admin Visibility​

  • VerboseName(label string): Human-friendly label displayed in the Admin UI.
  • HelpText(text string): Tooltip/help text displayed below input in the Admin UI.
  • Editable(bool): If false, disables field editing in the Admin UI and serializers.
  • Serialize(bool): If false, marks field as write-only (e.g. passwords).