main.go

package main

import (
	"context"
	"log"

	sqle "github.com/dolthub/go-mysql-server"
	"github.com/dolthub/go-mysql-server/memory"
	"github.com/dolthub/go-mysql-server/sql"
	"github.com/dolthub/go-mysql-server/sql/parse"
)

const (
	broken = `
select *
from contract c
         left join contracting_party cp on cp.id = c.counter_party_id

         left join contract_activities ca on ca.contract_id = c.id
         left join activity a on ca.activities_id = a.id
         left join comment_activity cac on cac.id = a.id
         left join document_update_activity dac on dac.id = a.id
         left join document_revision dr on dr.id = dac.document_revision_id
`

	working = `
select *
from contract c
         left join contracting_party cp on cp.id = c.counter_party_id

         left join contract_activities ca on ca.contract_id = c.id
         left join activity a on ca.activities_id = a.id
         left join comment_activity cac on cac.id = a.id
         -- left join document_update_activity dac on dac.id = a.id
         -- left join document_revision dr on dr.id = dac.document_revision_id
`
)

func runQuery(driver *sqle.Engine, query string) {
	ctx := sql.NewContext(context.Background())
	ctx.SetCurrentDatabase("test")

	plan, err := parse.Parse(ctx, query)
	if err != nil {
		log.Fatal(err, plan)
	}

	log.Print(plan.String())

	analyzed, err := driver.Analyzer.Analyze(ctx, plan, nil)
	if err != nil {
		log.Fatal(err, analyzed)
	}

	log.Print(analyzed.String())
}

func main() {
	db := memory.NewDatabase("test")

	tables := []sql.Table{
		memory.NewTable("contract", sql.Schema{
			{Name: "id", Type: sql.Int64, Source: "contract", PrimaryKey: true},
			{Name: "counter_party_id", Type: sql.Int64, Source: "contract"},
		}),
		memory.NewTable("activity", sql.Schema{
			{Name: "id", Type: sql.Int64, Source: "activity", PrimaryKey: true},
		}),
		memory.NewTable("contract_activities", sql.Schema{
			{Name: "contract_id", Type: sql.Int64, Source: "contract_activities"},
			{Name: "activities_id", Type: sql.Int64, Source: "contract_activities"},
		}),
		memory.NewTable("contracting_party", sql.Schema{
			{Name: "id", Type: sql.Int64, Source: "contracting_party", PrimaryKey: true},
		}),
		memory.NewTable("comment_activity", sql.Schema{
			{Name: "id", Type: sql.Int64, Source: "comment_activity", PrimaryKey: true},
		}),
		memory.NewTable("contract_document_revisions", sql.Schema{
			{Name: "contract_id", Type: sql.Int64, Source: "contract_document_revisions"},
			{Name: "document_revisions_id", Type: sql.Int64, Source: "contract_document_revisions"},
		}),
		memory.NewTable("document_revision", sql.Schema{
			{Name: "id", Type: sql.Int64, Source: "document_revision", PrimaryKey: true},
		}),
		memory.NewTable("document_update_activity", sql.Schema{
			{Name: "id", Type: sql.Int64, Source: "document_update_activity", PrimaryKey: true},
			{Name: "document_revision_id", Type: sql.Int64, Source: "document_update_activity"},
		}),
	}

	for _, table := range tables {
		db.AddTable(table.Name(), table)
	}

	driver := sqle.NewDefault()
	driver.AddDatabase(db)

	log.Println("Working query")
	runQuery(driver, working)

	log.Println("Broken query")
	runQuery(driver, broken)
}