Add support of OR REPLACE expression for CREATE TABLE|VIEW (#143)

Author: git-hulk

parser/ast.go

@@ -1516,6 +1516,7 @@ func (c *CreateDatabase) Accept(visitor ASTVisitor) error {
 type CreateTable struct {
 	CreatePos    Pos // position of CREATE|ATTACH keyword
 	StatementEnd Pos
+	OrReplace    bool
 	Name         *TableIdentifier
 	IfNotExists  bool
 	UUID         *UUID
@@ -1542,6 +1543,9 @@ func (c *CreateTable) Type() string {
 func (c *CreateTable) String() string {
 	var builder strings.Builder
 	builder.WriteString("CREATE")
+	if c.OrReplace {
+		builder.WriteString(" OR REPLACE")
+	}
 	if c.HasTemporary {
 		builder.WriteString(" TEMPORARY")
 	}
@@ -1706,6 +1710,7 @@ func (c *CreateMaterializedView) Accept(visitor ASTVisitor) error {
 type CreateView struct {
 	CreatePos    Pos // position of CREATE|ATTACH keyword
 	StatementEnd Pos
+	OrReplace    bool
 	Name         *TableIdentifier
 	IfNotExists  bool
 	UUID         *UUID
@@ -1728,7 +1733,11 @@ func (c *CreateView) Type() string {
 
 func (c *CreateView) String() string {
 	var builder strings.Builder
-	builder.WriteString("CREATE VIEW ")
+	builder.WriteString("CREATE")
+	if c.OrReplace {
+		builder.WriteString(" OR REPLACE")
+	}
+	builder.WriteString(" VIEW ")
 	if c.IfNotExists {
 		builder.WriteString("IF NOT EXISTS ")
 	}

parser/parser_common.go

@@ -61,6 +61,15 @@ func (p *Parser) matchKeyword(keyword string) bool {
 	return p.matchTokenKind(TokenKindKeyword) && strings.EqualFold(p.last().String, keyword)
 }
 
+func (p *Parser) matchOneOfKeywords(keywords ...string) bool {
+	for _, keyword := range keywords {
+		if p.matchKeyword(keyword) {
+			return true
+		}
+	}
+	return false
+}
+
 func (p *Parser) expectKeyword(keyword string) error {
 	if !p.matchKeyword(keyword) {
 		return fmt.Errorf("expected keyword: %s, but got %s", keyword, p.lastTokenKind())

parser/parser_table.go

@@ -9,28 +9,28 @@ func (p *Parser) parseDDL(pos Pos) (DDL, error) {
 	case p.matchKeyword(KeywordCreate),
 		p.matchKeyword(KeywordAttach):
 		_ = p.lexer.consumeToken()
+		orReplace := p.tryConsumeKeywords(KeywordOr, KeywordReplace)
+		if orReplace && !p.matchOneOfKeywords(KeywordTemporary, KeywordTable, KeywordView) {
+			return nil, fmt.Errorf("expected keyword: TEMPORARY|TABLE|VIEW, but got %q", p.last().String)
+		}
 		switch {
 		case p.matchKeyword(KeywordDatabase):
 			return p.parseCreateDatabase(pos)
 		case p.matchKeyword(KeywordTable),
 			p.matchKeyword(KeywordTemporary):
-			return p.parseCreateTable(pos)
+			return p.parseCreateTable(pos, orReplace)
 		case p.matchKeyword(KeywordFunction):
 			return p.parseCreateFunction(pos)
 		case p.matchKeyword(KeywordMaterialized):
 			return p.parseCreateMaterializedView(pos)
 		case p.matchKeyword(KeywordLive):
 			return p.parseCreateLiveView(pos)
 		case p.matchKeyword(KeywordView):
-			return p.parseCreateView(pos)
+			return p.parseCreateView(pos, orReplace)
 		case p.matchKeyword(KeywordRole):
 			return p.parseCreateRole(pos)
-		case p.matchKeyword(KeywordDictionary):
-		case p.matchKeyword(KeywordFunction):
-		case p.matchKeyword(KeywordRow):
-		case p.matchKeyword(KeywordSettings):
 		default:
-			return nil, fmt.Errorf("expected keyword: DATABASE|TABLE|VIEW|DICTIONARY|FUNCTION|ROW|QUOTA|SETTINGS, but got %q",
+			return nil, fmt.Errorf("expected keyword: DATABASE|TABLE|VIEW, but got %q",
 				p.last().String)
 		}
 	case p.matchKeyword(KeywordAlter):
@@ -108,9 +108,8 @@ func (p *Parser) parseCreateDatabase(pos Pos) (*CreateDatabase, error) {
 	}, nil
 }
 
-func (p *Parser) parseCreateTable(pos Pos) (*CreateTable, error) {
-	createTable := &CreateTable{CreatePos: pos}
-
+func (p *Parser) parseCreateTable(pos Pos, orReplace bool) (*CreateTable, error) {
+	createTable := &CreateTable{CreatePos: pos, OrReplace: orReplace}
 	createTable.HasTemporary = p.tryConsumeKeywords(KeywordTemporary)
 
 	if err := p.expectKeyword(KeywordTable); err != nil {

parser/parser_view.go

@@ -80,12 +80,12 @@ func (p *Parser) parseCreateMaterializedView(pos Pos) (*CreateMaterializedView,
 }
 
 // (ATTACH | CREATE) (OR REPLACE)? VIEW (IF NOT EXISTS)? tableIdentifier uuidClause? clusterClause? tableSchemaClause? subqueryClause
-func (p *Parser) parseCreateView(pos Pos) (*CreateView, error) {
+func (p *Parser) parseCreateView(pos Pos, orReplace bool) (*CreateView, error) {
+	createView := &CreateView{CreatePos: pos, OrReplace: orReplace}
 	if err := p.expectKeyword(KeywordView); err != nil {
 		return nil, err
 	}
 
-	createView := &CreateView{CreatePos: pos}
 	var err error
 	createView.IfNotExists, err = p.tryParseIfNotExists()
 	if err != nil {

parser/testdata/ddl/create_or_replace.sql

@@ -0,0 +1,23 @@
+-- It's a short link events table
+/**
+    * @name Short link events
+    * @description It's a short link events table
+ */
+CREATE OR REPLACE TABLE IF NOT EXISTS test.events_local (
+    f0 String,
+    f1 String CODEC(ZSTD(1)),
+    f2 VARCHAR(255),
+) ENGINE = MergeTree
+PRIMARY KEY (f0, f1, f2)
+PARTITION BY toYYYYMMDD(f1)
+TTL f1 + INTERVAL 6 MONTH
+ORDER BY (f1,f2)
+COMMENT 'Comment for table';
+
+CREATE OR REPLACE VIEW IF NOT EXISTS my_view(col1 String, col2 String)
+AS
+SELECT
+    id,
+    name
+FROM
+    my_table;

parser/testdata/ddl/format/create_or_replace.sql

@@ -0,0 +1,28 @@
+-- Origin SQL:
+-- It's a short link events table
+/**
+    * @name Short link events
+    * @description It's a short link events table
+ */
+CREATE OR REPLACE TABLE IF NOT EXISTS test.events_local (
+    f0 String,
+    f1 String CODEC(ZSTD(1)),
+    f2 VARCHAR(255),
+) ENGINE = MergeTree
+PRIMARY KEY (f0, f1, f2)
+PARTITION BY toYYYYMMDD(f1)
+TTL f1 + INTERVAL 6 MONTH
+ORDER BY (f1,f2)
+COMMENT 'Comment for table';
+
+CREATE OR REPLACE VIEW IF NOT EXISTS my_view(col1 String, col2 String)
+AS
+SELECT
+    id,
+    name
+FROM
+    my_table;
+
+-- Format SQL:
+CREATE OR REPLACE TABLE IF NOT EXISTS test.events_local (f0 String, f1 String CODEC(ZSTD(1)), f2 VARCHAR(255)) ENGINE = MergeTree PRIMARY KEY (f0, f1, f2) PARTITION BY toYYYYMMDD(f1) TTL f1 + INTERVAL 6 MONTH ORDER BY (f1, f2) COMMENT 'Comment for table';
+CREATE OR REPLACE VIEW IF NOT EXISTS my_view (col1 String, col2 String) AS SELECT id, name FROM my_table;

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

@@ -2,6 +2,7 @@
   {
     "CreatePos": 0,
     "StatementEnd": 399,
+    "OrReplace": false,
     "Name": {
       "Database": {
         "Name": "test",

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

@@ -2,6 +2,7 @@
   {
     "CreatePos": 0,
     "StatementEnd": 191,
+    "OrReplace": false,
     "Name": {
       "Database": {
         "Name": "test",