Add MOVE PARTITION and fix OPTIMIZE TABLE database name

- Added MOVE PARTITION ... TO TABLE parsing in ALTER statements
- Added ToDatabase and ToTable fields to AlterCommand for destination
- Fixed OPTIMIZE TABLE to output database identifier for qualified names

Author: claude

ast/ast.go

@@ -578,7 +578,9 @@ type AlterCommand struct {
 	Partition      Expression           `json:"partition,omitempty"`
 	PartitionIsID  bool                 `json:"partition_is_id,omitempty"` // True when using PARTITION ID 'value' syntax
 	FromTable      string               `json:"from_table,omitempty"`
-	FromPath       string               `json:"from_path,omitempty"` // For FETCH PARTITION FROM
+	ToDatabase     string               `json:"to_database,omitempty"` // For MOVE PARTITION TO TABLE
+	ToTable        string               `json:"to_table,omitempty"`    // For MOVE PARTITION TO TABLE
+	FromPath       string               `json:"from_path,omitempty"`   // For FETCH PARTITION FROM
 	TTL            *TTLClause           `json:"ttl,omitempty"`
 	Settings       []*SettingExpr       `json:"settings,omitempty"`
 	Where          Expression           `json:"where,omitempty"`       // For DELETE WHERE

internal/explain/statements.go

@@ -1610,15 +1610,26 @@ func explainOptimizeQuery(sb *strings.Builder, n *ast.OptimizeQuery, indent stri
 	}
 
 	children := 1 // identifier
+	if n.Database != "" {
+		children++ // extra identifier for database
+	}
 	if n.Partition != nil {
 		children++
 	}
 
-	fmt.Fprintf(sb, "%sOptimizeQuery  %s (children %d)\n", indent, name, children)
+	if n.Database != "" {
+		// Database-qualified: OptimizeQuery db table (children N)
+		fmt.Fprintf(sb, "%sOptimizeQuery %s %s (children %d)\n", indent, n.Database, name, children)
+	} else {
+		fmt.Fprintf(sb, "%sOptimizeQuery  %s (children %d)\n", indent, name, children)
+	}
 	if n.Partition != nil {
 		fmt.Fprintf(sb, "%s Partition (children 1)\n", indent)
 		Node(sb, n.Partition, depth+2)
 	}
+	if n.Database != "" {
+		fmt.Fprintf(sb, "%s Identifier %s\n", indent, n.Database)
+	}
 	fmt.Fprintf(sb, "%s Identifier %s\n", indent, n.Table)
 }
 

parser/parser.go

@@ -4712,6 +4712,34 @@ func (p *Parser) parseAlterCommand() *ast.AlterCommand {
 				cmd.Type = ast.AlterMaterializeTTL
 				p.nextToken()
 			}
+		} else if upper == "MOVE" {
+			p.nextToken()
+			if p.currentIs(token.PARTITION) {
+				cmd.Type = ast.AlterMovePartition
+				p.nextToken()
+				// Check for PARTITION ID 'value' syntax
+				if p.currentIs(token.IDENT) && strings.ToUpper(p.current.Value) == "ID" {
+					p.nextToken()
+					cmd.PartitionIsID = true
+				}
+				cmd.Partition = p.parseExpression(LOWEST)
+				// Parse TO TABLE destination
+				if p.currentIs(token.TO) {
+					p.nextToken()
+					if p.currentIs(token.TABLE) {
+						p.nextToken()
+					}
+					// Parse destination table (can be qualified: database.table)
+					destName := p.parseIdentifierName()
+					if p.currentIs(token.DOT) {
+						p.nextToken()
+						cmd.ToDatabase = destName
+						cmd.ToTable = p.parseIdentifierName()
+					} else {
+						cmd.ToTable = destName
+					}
+				}
+			}
 		} else {
 			return nil
 		}

parser/testdata/00753_alter_attach/metadata.json

@@ -1,6 +1,5 @@
 {
   "explain_todo": {
-    "stmt52": true,
     "stmt53": true,
     "stmt54": true,
     "stmt55": true,

parser/testdata/01765_move_to_table_overlapping_block_number/metadata.json

@@ -1,5 +1 @@
-{
-  "explain_todo": {
-    "stmt11": true
-  }
-}
+{}

parser/testdata/01818_move_partition_simple/metadata.json

@@ -1,5 +1 @@
-{
-  "explain_todo": {
-    "stmt16": true
-  }
-}
+{}

parser/testdata/02028_add_default_database_for_alterquery_on_cluster/metadata.json

@@ -1,5 +1 @@
-{
-  "explain_todo": {
-    "stmt11": true
-  }
-}
+{}

parser/testdata/02486_truncate_and_unexpected_parts/metadata.json

@@ -1,7 +1,6 @@
 {
   "explain_todo": {
     "stmt24": true,
-    "stmt26": true,
     "stmt43": true,
     "stmt44": true
   }

parser/testdata/02915_move_partition_inactive_replica/metadata.json

@@ -1,11 +1 @@
-{
-  "explain_todo": {
-    "stmt22": true,
-    "stmt23": true,
-    "stmt24": true,
-    "stmt25": true,
-    "stmt26": true,
-    "stmt27": true,
-    "stmt28": true
-  }
-}
+{}

parser/testdata/02916_another_move_partition_inactive_replica/metadata.json

@@ -1,7 +1 @@
-{
-  "explain_todo": {
-    "stmt19": true,
-    "stmt22": true,
-    "stmt23": true
-  }
-}
+{}