Fix missing DROP keyword in alter table drop clause (#81)

Author: laojianzi

parser/ast.go

@@ -324,15 +324,20 @@ func (a *AlterTableDetachPartition) Accept(visitor ASTVisitor) error {
 }
 
 type AlterTableDropPartition struct {
-	DropPos   Pos
-	Partition *PartitionClause
+	DropPos     Pos
+	HasDetached bool
+	Partition   *PartitionClause
+	Settings    *SettingsClause
 }
 
 func (a *AlterTableDropPartition) Pos() Pos {
 	return a.DropPos
 }
 
 func (a *AlterTableDropPartition) End() Pos {
+	if a.Settings != nil {
+		a.Settings.End()
+	}
 	return a.Partition.End()
 }
 
@@ -343,7 +348,14 @@ func (a *AlterTableDropPartition) AlterType() string {
 func (a *AlterTableDropPartition) String(level int) string {
 	var builder strings.Builder
 	builder.WriteString("DROP ")
+	if a.HasDetached {
+		builder.WriteString("DETACHED ")
+	}
 	builder.WriteString(a.Partition.String(level))
+	if a.Settings != nil {
+		builder.WriteByte(' ')
+		builder.WriteString(a.Settings.String(level))
+	}
 	return builder.String()
 }
 

parser/parser_alter.go

@@ -295,10 +295,7 @@ func (p *Parser) parseAlterTableDrop(pos Pos) (AlterTableClause, error) {
 	switch {
 	case p.matchKeyword(KeywordColumn), p.matchKeyword(KeywordIndex), p.matchKeyword(KeywordProjection):
 		return p.parseAlterTableDropClause(pos)
-	case p.matchKeyword(KeywordDetached):
-		_ = p.lexer.consumeToken()
-		return p.parseAlterTableDetachPartition(pos)
-	case p.matchKeyword(KeywordPartition):
+	case p.matchKeyword(KeywordDetached), p.matchKeyword(KeywordPartition):
 		return p.parseAlterTableDropPartition(pos)
 	default:
 		return nil, errors.New("expected keyword: COLUMN|INDEX|PROJECTION|DETACHED|PARTITION")
@@ -443,6 +440,11 @@ func (p *Parser) tryParseAfterClause() (*NestedIdentifier, error) {
 
 // Syntax: ALTER TABLE DROP partitionClause
 func (p *Parser) parseAlterTableDropPartition(pos Pos) (AlterTableClause, error) {
+	var hasDetached bool
+	if p.matchKeyword(KeywordDetached) {
+		_ = p.lexer.consumeToken()
+		hasDetached = true
+	}
 	partitionPos := p.Pos()
 	if err := p.consumeKeyword(KeywordPartition); err != nil {
 		return nil, err
@@ -456,9 +458,16 @@ func (p *Parser) parseAlterTableDropPartition(pos Pos) (AlterTableClause, error)
 	}
 	partition.Expr = expr
 
+	settings, err := p.tryParseSettingsClause(p.Pos())
+	if err != nil {
+		return nil, err
+	}
+
 	return &AlterTableDropPartition{
-		DropPos:   pos,
-		Partition: partition,
+		DropPos:     pos,
+		Partition:   partition,
+		HasDetached: hasDetached,
+		Settings:    settings,
 	}, nil
 }
 

parser/testdata/ddl/format/alter_table_drop_detach_partition.sql

@@ -3,4 +3,4 @@ ALTER TABLE app_utc_00.app_message_as_notification_organization_sent_stats_i_d_l
 
 -- Format SQL:
 ALTER TABLE app_utc_00.app_message_as_notification_organization_sent_stats_i_d_local
-DETACH PARTITION '2022-05-24' SETTINGS allow_drop_detached=1;
+DROP DETACHED PARTITION '2022-05-24' SETTINGS allow_drop_detached=1;

parser/testdata/ddl/output/alter_table_drop_detach_partition.sql.golden.json

@@ -19,7 +19,8 @@
     "OnCluster": null,
     "AlterExprs": [
       {
-        "DetachPos": 85,
+        "DropPos": 85,
+        "HasDetached": true,
         "Partition": {
           "PartitionPos": 99,
           "Expr": {

parser/testdata/ddl/output/alter_table_drop_partition.sql.golden.json

@@ -27,6 +27,7 @@
     "AlterExprs": [
       {
         "DropPos": 53,
+        "HasDetached": false,
         "Partition": {
           "PartitionPos": 58,
           "Expr": {
@@ -36,7 +37,8 @@
           },
           "ID": null,
           "All": false
-        }
+        },
+        "Settings": null
       }
     ]
   }