JustTheSyme
JustTheSyme
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DTDrizzle Team
Created by JustTheSyme on 1/5/2024 in #help
How to type a function with column key of table
I can't get this to type correctly. I want field to be a column of table, but typescript keeps saying Type 'Field' cannot be used to index type 'TTable'. What's the best way to do this? 
type GetColumnKeys<TTable extends Table> = keyof {
  [K in keyof TTable as K extends keyof TTable['_']['columns'] ? K : never]: true
}

async function getOptions<
  TTable extends Table,
  Field extends GetColumnKeys<TTable>
>(table: TTable, field: Field) {
  const column = table[field]
  const result = await drizzleDb
    .selectDistinct({
      option: column
    })
    .from(table)
    .orderBy(column)
  return result.map((i) => String(i.option))
}
type GetColumnKeys<TTable extends Table> = keyof {
  [K in keyof TTable as K extends keyof TTable['_']['columns'] ? K : never]: true
}

async function getOptions<
  TTable extends Table,
  Field extends GetColumnKeys<TTable>
>(table: TTable, field: Field) {
  const column = table[field]
  const result = await drizzleDb
    .selectDistinct({
      option: column
    })
    .from(table)
    .orderBy(column)
  return result.map((i) => String(i.option))
}
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