INDEX_UNIQUE
All functions > ARRAY_OF_ROWS > INDEX_UNIQUE
Returns an index unique computed from the given array and key.
Syntax
INDEX_UNIQUE(base: ARRAY<ROW<T>>, key: FIELD) → INDEXsql
Type Parameters:
T: Any row type with named fields
Arguments
| Parameter | Type | Required | Description |
|---|---|---|---|
base | ARRAY<ROW<T>> | Yes | Array of rows to index |
key | FIELD | Yes | Field name to use as lookup key |
Returns
INDEX - Map from key values to array positions (1-based)
Notes
- Creates a unique index mapping key values to array positions
- Each key maps to at most one position (the last occurrence if duplicates exist)
- Returns 1-based array indices
- NULL keys are excluded from the index
- Useful for efficient lookups with ELEMENT_AT_KEY
- If duplicate keys exist, keeps the last occurrence
- Use INDEX_MULTI for keys with multiple values