upsert doUpdate max not matching readme?

[jubishop]

in the readme I can't seem to make this work:

Column("date").set(to: max(Column("date"), excluded["date"])

it appears I can only specify one argument to max or a second with the keyword filter. Am I missing something?

thanks!

[groue]

Hello @jubishop,

Thank you for the report! This is both a documentation bug, and a missing feature.

The sample code is misleading, because GRDB does not ship with the MAX(X,Y,...) multi-argument function. When one writes max, it refers to the MAX(X) aggregate function.

If you need the multi-argument function right now, you can define it yourself, until the library ships a new version that includes it:

func max(
    _ arg1: any SQLSpecificExpressible,
    _ arg2: any SQLExpressible,
    _ args: any SQLExpressible...
) -> SQLExpression {
    var sql: SQL = "MAX(\(arg1), \(arg2)"
    for arg in args {
        sql += ", \(arg)"
    }
    sql += ")"
    return sql.sqlExpression
}

[jubishop]

Ahh that makes sense thanks!!