func (no *NaiveOptimizer) MoveWhereToDataSource(plan planner.Plan) {
// look for a WHERE clause immediately followed by a data source
// then ask the datasource if can support this WHERE clause
// if it can, have it do so, and remove the in memory WHERE
var last planner.PlanPipelineComponent
curr := plan.Root.GetSource()
for curr != nil {
switch currFilter := curr.(type) {
case planner.Filter:
next := curr.GetSource()
switch nextDataSource := next.(type) {
case planner.DataSource:
//log.Printf("Found where clause immidiately followed by datasource %v", last)
err := nextDataSource.SetFilter(currFilter.GetFilter())
if err != nil {
//log.Printf("this datasource cannot support this filter")
} else {
//log.Printf("datasource accepted the filter, removing old filter")
if last == nil {
plan.Root.SetSource(next)
} else {
last.SetSource(next)
}
}
}
}
last = curr
curr = curr.GetSource()
}
}
func (no *NaiveOptimizer) MoveGroupByToDataSource(plan planner.Plan) {
// look for a GROUP BY clause immediately followed by a data source
// then ask the datasource if it can support this GROUP BY clause
// if it can, have it do so, and remove the in memory GROUP BY
var last planner.PlanPipelineComponent
curr := plan.Root.GetSource()
for curr != nil {
switch currGrouper := curr.(type) {
case planner.Grouper:
next := curr.GetSource()
switch nextDataSource := next.(type) {
case planner.DataSource:
//log.Printf("Found group by clause immidiately followed by datasource %v", last)
err := nextDataSource.SetGroupByWithStatsFields(currGrouper.GetGroupByWithStatsFields())
if err != nil {
//log.Printf("this datasource cannot support this group by")
} else {
//log.Printf("datasource accepted the group by, removing old group by")
if last == nil {
plan.Root.SetSource(next)
} else {
last.SetSource(next)
}
}
}
}
last = curr
curr = curr.GetSource()
}
}
func (no *NaiveOptimizer) MoveOffsetToDataSource(plan planner.Plan) {
// look for a OFFSET clause immediately followed by a data source
// then ask the datasource if it can support this OFFSET clause
// if it can, have it do so, and remove the in memory OFFSET
var last planner.PlanPipelineComponent
curr := plan.Root.GetSource()
for curr != nil {
switch currOffsetter := curr.(type) {
case planner.Offsetter:
next := curr.GetSource()
switch nextDataSource := next.(type) {
case planner.DataSource:
//log.Printf("Found offset clause immidiately followed by datasource %v", last)
err := nextDataSource.SetOffset(currOffsetter.GetOffset())
if err != nil {
//log.Printf("this datasource cannot support this offset")
} else {
//log.Printf("datasource accepted the offset, removing old group by")
if last == nil {
plan.Root.SetSource(next)
} else {
last.SetSource(next)
}
}
}
}
last = curr
curr = curr.GetSource()
}
}
