drizzle-team/drizzle-orm · error · Error

column with type ${col.baseColumn!.columnType} is not suppor

Error message

column with type ${col.baseColumn!.columnType} is not supported for now.

What it means

In selectGeneratorForPostgresColumn, when a column is a Postgres array (columnType matches [/\[\w*]/]) with a defined baseColumn, the resolver recurses to find a generator for the base (element) type. If the base column type is unsupported and returns undefined, the array generator cannot be constructed and it throws.

Source

Thrown at drizzle-seed/src/services/SeedService.ts:515

		}

		return weightedWithCount;
	};

	// TODO: revise serial part generators
	selectGeneratorForPostgresColumn = (
		table: Table,
		col: Column,
	) => {
		const pickGenerator = (table: Table, col: Column) => {
			// ARRAY
			if (col.columnType.match(/\[\w*]/g) !== null && col.baseColumn !== undefined) {
				const baseColumnGen = this.selectGeneratorForPostgresColumn(
					table,
					col.baseColumn!,
				) as AbstractGenerator;
				if (baseColumnGen === undefined) {
					throw new Error(`column with type ${col.baseColumn!.columnType} is not supported for now.`);
				}

				// const getBaseColumnDataType = (baseColumn: Column) => {
				// 	if (baseColumn.baseColumn !== undefined) {
				// 		return getBaseColumnDataType(baseColumn.baseColumn);
				// 	}

				// 	return baseColumn.dataType;
				// };
				// const baseColumnDataType = getBaseColumnDataType(col.baseColumn);

				const generator = new generatorsMap.GenerateArray[0]({ baseColumnGen, size: col.size });
				// generator.baseColumnDataType = baseColumnDataType;

				return generator;
			}

			// ARRAY for studio

View on GitHub (pinned to b7862528fd)

Solutions

Provide a refinement generator for the array column so the auto-resolver is bypassed.
Change the array's element type to a supported primitive (text, integer, etc.).
Make the column nullable and leave it unrefined so it defaults to null.

Example fix

// before
keywords: customType('keywords').array()
// after — refine with a generator
refinements = {
  myTable: {
    columns: {
      keywords: { generator: generators.array({ values: ['a','b','c'] }) }
    }
  }
};

Defensive patterns

Strategy: validation

Validate before calling

// Check whether a Postgres array column's base type is supported.
const SUPPORTED_SCALAR_TYPES = ['serial','integer','smallint','bigint','varchar','text','boolean','date','timestamp','numeric','real','double','json','jsonb','uuid','interval'];
function isArrayBaseSupported(columnType: string): boolean {
  if (!columnType.match(/\[\w*\]/)) return true; // not an array
  const baseType = columnType.replace(/\[\w*\]/g, '');
  return SUPPORTED_SCALAR_TYPES.some((t) => baseType.includes(t));
}
// If false, supply a refinement generator for the column.

Prevention

Use arrays of standard scalar types (text[], integer[]) for seedable columns.
Provide refinement generators for arrays of custom or exotic types.
Make unsupported array columns nullable so they default to null.

When it happens

Trigger: A Postgres array column whose element type has no generator (e.g. tsvector[], custom_type[], bit varying[]) and no refinement is supplied for the column.

Common situations: Schema with typed arrays of exotic Postgres types; using array of a UDT or domain that drizzle-seed cannot resolve.

Related errors

AI-assisted analysis of drizzle-team/drizzle-orm@b7862528fd (2026-08-03). Data as JSON: /data/errors/d7333cd1855ede99.json. Report an issue: GitHub.