Named Parameters

SQLiteNow infers parameter types by analysing how each named argument is used. When a parameter binds directly to a column, the generator picks up the type automatically. Complex expressions, WITH clauses, or functions can hide that context and default the parameter to String.

Use explicit casts to steer the generator toward the correct Kotlin type.

Enforcing numeric types in date calculations

Consider a query that derives a date range from :year and :month arguments:

WITH range AS (
  SELECT
    (julianday(printf('%04d-%02d-01', :year, :month)) - julianday('1970-01-01')) AS start_days,
    (julianday(date(printf('%04d-%02d-01', :year, :month), '+1 month')) - julianday('1970-01-01')) AS end_days
)
SELECT *
FROM daily_log
WHERE log_date >= (SELECT start_days FROM range)
  AND log_date <  (SELECT end_days FROM range);

Because :year and :month never bind to a column directly, the generator cannot infer their types and defaults to String.

Add explicit casts to guide type inference:

WITH range AS (
  SELECT
    (julianday(printf('%04d-%02d-01', CAST(:year AS INTEGER), CAST(:month AS INTEGER))) - julianday('1970-01-01')) AS start_days,
    (julianday(date(printf('%04d-%02d-01', :year, :month), '+1 month')) - julianday('1970-01-01')) AS end_days
)
SELECT *
FROM daily_log
WHERE log_date >= (SELECT start_days FROM range)
  AND log_date <  (SELECT end_days FROM range);

With the casts in place, SQLiteNow detects that both parameters should be numeric (Int/Long depending on your schema), and the generated Params data class uses the appropriate Kotlin type.

When to cast parameters

Parameters used only inside SQL functions (julianday, strftime, etc.)
Expressions inside WITH CTEs that never bind to a physical column
JSON or math functions that strip the original column context

When in doubt, casting to the expected column type prevents accidental String fallbacks and keeps your API strongly typed.