func findColumnIndexByGroup(groups []LogicalPlan, col *expression.Column) int {
for i, plan := range groups {
idx := plan.GetSchema().GetIndex(col)
if idx != -1 {
return i
}
}
log.Errorf("Unknown columns %s, from id %s, position %d", col.ToString(), col.FromID, col.Position)
return -1
}
