remove exchange node (#2715)

Author: jycor

enginetest/harness.go

@@ -35,8 +35,6 @@ import (
 // times during a single test run, and must return a "fresh" engine instance each time, i.e. an instance that contains
 // exactly the test data provided via other setup methods.
 type Harness interface {
-	// Parallelism returns how many parallel go routines to use when constructing an engine for test.
-	Parallelism() int
 	// NewContext allows a harness to specify any sessions or context variables necessary for the proper functioning of
 	// their engine implementation. Every harnessed engine test uses the context created by this method, with some
 	// additional information (e.g. current DB) set uniformly. To replicate the behavior of tests during setup,

enginetest/initialization.go

@@ -37,11 +37,6 @@ func NewContextWithClient(harness ClientHarness, client sql.Client) *sql.Context
 	return newContextSetup(harness.NewContextWithClient(client))
 }
 
-// TODO: remove
-func NewContextWithEngine(harness Harness, engine QueryEngine) *sql.Context {
-	return NewContext(harness)
-}
-
 var pid uint64
 
 func newContextSetup(ctx *sql.Context) *sql.Context {
@@ -84,22 +79,15 @@ func NewBaseSession() *sql.BaseSession {
 
 // NewEngineWithProvider returns a new engine with the specified provider
 func NewEngineWithProvider(_ *testing.T, harness Harness, provider sql.DatabaseProvider) *sqle.Engine {
-	var a *analyzer.Analyzer
-
-	if harness.Parallelism() > 1 {
-		a = analyzer.NewBuilder(provider).WithParallelism(harness.Parallelism()).Build()
-	} else {
-		a = analyzer.NewDefault(provider)
-	}
+	analyzer := analyzer.NewDefault(provider)
 
 	// All tests will run with all privileges on the built-in root account
-	a.Catalog.MySQLDb.AddRootAccount()
+	analyzer.Catalog.MySQLDb.AddRootAccount()
 	// Almost no tests require an information schema that can be updated, but test setup makes it difficult to not
 	// provide everywhere
-	a.Catalog.InfoSchema = information_schema.NewInformationSchemaDatabase()
-
-	engine := sqle.New(a, new(sqle.Config))
+	analyzer.Catalog.InfoSchema = information_schema.NewInformationSchemaDatabase()
 
+	engine := sqle.New(analyzer, new(sqle.Config))
 	if idh, ok := harness.(IndexDriverHarness); ok {
 		idh.InitializeIndexDriver(engine.Analyzer.Catalog.AllDatabases(NewContext(harness)))
 	}

enginetest/memory_engine_test.go

@@ -484,10 +484,6 @@ func TestIndexQueryPlans(t *testing.T) {
 	}
 }
 
-func TestParallelismQueries(t *testing.T) {
-	enginetest.TestParallelismQueries(t, enginetest.NewMemoryHarness("default", 2, testNumPartitions, true, nil))
-}
-
 func TestQueryErrors(t *testing.T) {
 	enginetest.TestQueryErrors(t, enginetest.NewDefaultMemoryHarness())
 }

enginetest/parallelism.go

@@ -164,7 +164,7 @@ func generatePlansForSuite(spec PlanSpec, w *bytes.Buffer) error {
 		_, _ = w.WriteString("\n")
 
 		if !tt.Skip {
-			ctx := enginetest.NewContextWithEngine(harness, engine)
+			ctx := enginetest.NewContext(harness)
 			binder := planbuilder.New(ctx, engine.EngineAnalyzer().Catalog, sql.NewMysqlParser())
 			parsed, _, _, qFlags, err := binder.Parse(tt.Query, nil, false)
 			if err != nil {

enginetest/plangen/cmd/plangen/main.go

@@ -74,7 +74,6 @@ type Builder struct {
 	afterAllRules       []Rule
 	provider            sql.DatabaseProvider
 	debug               bool
-	parallelism         int
 }
 
 // NewBuilder creates a new Builder from a specific catalog.
@@ -100,12 +99,6 @@ func (ab *Builder) WithDebug() *Builder {
 	return ab
 }
 
-// WithParallelism sets the parallelism level on the analyzer.
-func (ab *Builder) WithParallelism(parallelism int) *Builder {
-	ab.parallelism = parallelism
-	return ab
-}
-
 // AddPreAnalyzeRule adds a new rule to the analyze before the standard analyzer rules.
 func (ab *Builder) AddPreAnalyzeRule(id RuleId, fn RuleFunc) *Builder {
 	ab.preAnalyzeRules = append(ab.preAnalyzeRules, Rule{id, fn})
@@ -271,7 +264,6 @@ func (ab *Builder) Build() *Analyzer {
 		contextStack: make([]string, 0),
 		Batches:      batches,
 		Catalog:      NewCatalog(ab.provider),
-		Parallelism:  ab.parallelism,
 		Coster:       memo.NewDefaultCoster(),
 		ExecBuilder:  rowexec.DefaultBuilder,
 	}
@@ -286,7 +278,6 @@ type Analyzer struct {
 	Verbose bool
 	// A stack of debugger context. See PushDebugContext, PopDebugContext
 	contextStack []string
-	Parallelism  int
 	// Batches of Rules to apply.
 	Batches []*Batch
 	// Catalog of databases and registered functions.
@@ -304,7 +295,6 @@ type Analyzer struct {
 // To add custom rules, the easiest way is use the Builder.
 func NewDefault(provider sql.DatabaseProvider) *Analyzer {
 	return NewBuilder(provider).Build()
-
 }
 
 // NewDefaultWithVersion creates a default Analyzer instance either
@@ -402,10 +392,8 @@ func NewProcRuleSelector(sel RuleSelector) RuleSelector {
 		switch id {
 		case pruneTablesId,
 			unnestInSubqueriesId,
-
 			// once after default rules should only be run once
-			TrackProcessId,
-			parallelizeId:
+			TrackProcessId:
 			return false
 		}
 		return sel(id)
@@ -452,8 +440,7 @@ func NewFinalizeUnionSel(sel RuleSelector) RuleSelector {
 		case
 			// skip recursive resolve rules
 			resolveSubqueriesId,
-			resolveUnionsId,
-			parallelizeId:
+			resolveUnionsId:
 			return false
 		case finalizeSubqueriesId,
 			hoistOutOfScopeFiltersId: