Function inferSchemaFromCsv

apps/sim/lib/table/import.ts:185–211

(
  headers: string[],
  rows: Record<string, unknown>[]
)

 * column-name mapping used when coercing row values.
 */
export function inferSchemaFromCsv(
  headers: string[],
  rows: Record<string, unknown>[]
): { columns: ColumnDefinition[]; headerToColumn: Map<string, string> } {
  const sample = rows.slice(0, CSV_SCHEMA_SAMPLE_SIZE)
  const seen = new Set<string>()
  const headerToColumn = new Map<string, string>()

  const columns = headers.map((header) => {
    const base = sanitizeName(header)
    let colName = base
    let suffix = 2
    while (seen.has(colName.toLowerCase())) {
      colName = `${base}_${suffix}`
      suffix++
    }
    seen.add(colName.toLowerCase())
    headerToColumn.set(header, colName)

    return {
      name: colName,
      type: inferColumnType(sample.map((r) => r[header])),
    } satisfies ColumnDefinition
  })

  return { columns, headerToColumn }
}

/**
 * Coerces a single value to the requested column type. Returns `null` for