Support uint64 parameters

[xaprb]

According to Russ Cox, uint64 with high bits set would work with a custom ColumnConverter. Is this a reasonable feature to add to this driver? See "Large uint64 Values" on http://go-database-sql.org/surprises.html for why this might be a problem worth solving.

[arnehormann]

UPDATE I'm right concerning "I'm blind". The whole issue is about parameters, not (result) columns. And ColumnConverter is curiously named. I deleted some output from below and I'l have another go at this.

I'm think I'm blind right now, please help!
I just wrote this:

func TestUint64(t *testing.T) {
    const (
        u0    = uint64(0)
        uall  = ^u0
        uhigh = uall >> 1
        utop  = ^uhigh
        s0    = int64(0)
        sall  = ^s0
        shigh = int64(uhigh)
        stop  = ^shigh
    )
    runTests(t, dsn, func(dbt *DBTest) {
        query := fmt.Sprintf(
            `SELECT
                cast(%d as unsigned), cast(%d as unsigned), cast(%d as unsigned), cast(%d as unsigned),
                cast(%d as signed), cast(%d as signed), cast(%d as signed), cast(%d as signed)`,
            u0, uhigh, utop, uall,
            s0, shigh, stop, sall,
        )
        // use Prepare to force binary protocol
        stmt, err := dbt.db.Prepare(query)
        if err != nil {
            dbt.Fatal("Could not prepare query")
        }
        defer stmt.Close()
        row := stmt.QueryRow()

        var ua, ub, uc, ud uint64
        var sa, sb, sc, sd int64

        err = row.Scan(&ua, &ub, &uc, &ud, &sa, &sb, &sc, &sd)
        if err != nil {
            dbt.Fatal("Could not retrieve results")
        }
        /*
            dbt.Errorf("Query: %s\n\t%d\n\t%d\n\t%d\n\t%d\n\t%d\n\t%d\n\t%d\n\t%d",
                query,
                ua, ub, uc, ud,
                sa, sb, sc, sd,
            )
        */
        switch {
        case ua != u0,
            ub != uhigh,
            uc != utop,
            ud != uall,
            sa != s0,
            sb != shigh,
            sc != stop,
            sd != sall:
            dbt.Fatal("Unexpected result")
        }
    })
}

[... more rambling followed before my edit]

[xaprb]

It's not on Scan() that there's a problem; it's like this: db.Exec("insert into tbl values(?)", uall)

[arnehormann]

I know, I'm on it. This is the new test.

func TestUint64(t *testing.T) {
    const (
        u0    = uint64(0)
        uall  = ^u0
        uhigh = uall >> 1
        utop  = ^uhigh
        s0    = int64(0)
        sall  = ^s0
        shigh = int64(uhigh)
        stop  = ^shigh
    )
    runTests(t, dsn, func(dbt *DBTest) {
        row := dbt.db.QueryRow(
            `SELECT ?, ?, ? ,?, ?, ?, ?, ?`,
            u0, uhigh, utop, uall,
            s0, shigh, stop, sall,
        )

        var ua, ub, uc, ud uint64
        var sa, sb, sc, sd int64

        err := row.Scan(&ua, &ub, &uc, &ud, &sa, &sb, &sc, &sd)
        if err != nil {
            dbt.Fatal(err)
        }
        switch {
        case ua != u0,
            ub != uhigh,
            uc != utop,
            ud != uall,
            sa != s0,
            sb != shigh,
            sc != stop,
            sd != sall:
            dbt.Fatal("Unexpected result value")
        }
    })
}

The solution is also done in principle. Just wrangling with Go (somehow it doesn't want to call my ColumnConverter, but I'll get there).