Support DESCRIBE TABLE syntax (#183)

Author: dejanmltc

parser/ast.go

@@ -8338,6 +8338,7 @@ func (s *ShowStmt) Accept(visitor ASTVisitor) error {
 type DescribeStmt struct {
 	DescribePos  Pos
 	StatementEnd Pos
+	DescribeType string // e.g., "TABLE", empty if not used
 	Target       *TableIdentifier
 }
 
@@ -8352,6 +8353,10 @@ func (d *DescribeStmt) End() Pos {
 func (d *DescribeStmt) String() string {
 	var builder strings.Builder
 	builder.WriteString("DESCRIBE ")
+	if d.DescribeType != "" {
+		builder.WriteString(d.DescribeType)
+		builder.WriteString(" ")
+	}
 	builder.WriteString(d.Target.String())
 	return builder.String()
 }

parser/parser_table.go

@@ -1308,6 +1308,13 @@ func (p *Parser) parseDescribeStmt(pos Pos) (*DescribeStmt, error) {
 	}
 	_ = p.lexer.consumeToken()
 
+	// TABLE keyword is optional after DESC/DESCRIBE
+	var describeType string
+	if p.matchKeyword(KeywordTable) {
+		_ = p.lexer.consumeToken()
+		describeType = "TABLE"
+	}
+
 	tableIdent, err := p.parseTableIdentifier(p.Pos())
 	if err != nil {
 		return nil, err
@@ -1316,6 +1323,7 @@ func (p *Parser) parseDescribeStmt(pos Pos) (*DescribeStmt, error) {
 	return &DescribeStmt{
 		DescribePos:  pos,
 		StatementEnd: tableIdent.End(),
+		DescribeType: describeType,
 		Target:       tableIdent,
 	}, nil
 }

parser/testdata/ddl/desc_table_with_table_keyword.sql

@@ -0,0 +1 @@
+DESC TABLE mytable

parser/testdata/ddl/desc_table.sql …ddl/desc_table_without_table_keyword.sqlparser/testdata/ddl/desc_table.sql renamed to parser/testdata/ddl/desc_table_without_table_keyword.sql parser/testdata/ddl/desc_table.sql renamed to parser/testdata/ddl/desc_table_without_table_keyword.sql

@@ -0,0 +1 @@
+DESCRIBE TABLE mytable

parser/testdata/ddl/describe_table_with_table_keyword.sql

@@ -1,5 +1,5 @@
 -- Origin SQL:
-DESC mytable
+DESC TABLE mytable
 
 -- Format SQL:
-DESCRIBE mytable;
+DESCRIBE TABLE mytable;

parser/testdata/ddl/describe_table.sql …describe_table_without_table_keyword.sqlparser/testdata/ddl/describe_table.sql renamed to parser/testdata/ddl/describe_table_without_table_keyword.sql parser/testdata/ddl/describe_table.sql renamed to parser/testdata/ddl/describe_table_without_table_keyword.sql

@@ -0,0 +1,5 @@
+-- Origin SQL:
+DESC TABLE mytable
+
+-- Format SQL:
+DESCRIBE TABLE mytable;

parser/testdata/ddl/format/desc_table.sql

@@ -0,0 +1,5 @@
+-- Origin SQL:
+DESC mytable
+
+-- Format SQL:
+DESCRIBE mytable;

parser/testdata/ddl/format/desc_table_with_table_keyword.sql

@@ -1,5 +1,5 @@
 -- Origin SQL:
-DESCRIBE mytable
+DESCRIBE TABLE mytable
 
 -- Format SQL:
-DESCRIBE mytable;
+DESCRIBE TABLE mytable;