support pgsql truncate statement

src/main/java/com/alibaba/druid/sql/ast/statement/SQLTruncateStatement.java

@@ -0,0 +1,29 @@
+package com.alibaba.druid.sql.ast.statement;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.alibaba.druid.sql.ast.SQLName;
+import com.alibaba.druid.sql.ast.SQLStatementImpl;
+import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+
+public class SQLTruncateStatement extends SQLStatementImpl {
+
+    private static final long serialVersionUID = 1L;
+    protected List<SQLName>           tableNames = new ArrayList<SQLName>(2);
+
+    public List<SQLName> getTableNames() {
+        return tableNames;
+    }
+
+    public void setTableNames(List<SQLName> tableNames) {
+        this.tableNames = tableNames;
+    }
+
+    @Override
+    protected void accept0(SQLASTVisitor visitor) {
+        if (visitor.visit(this)) {
+            acceptChild(visitor, tableNames);
+        }
+    }
+}

src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlLexer.java

@@ -103,6 +103,7 @@ public class MySqlLexer extends Lexer {
         map.put("LOCK", Token.LOCK);
         map.put("SOME", Token.SOME);
         map.put("ANY", Token.ANY);
+        map.put("TRUNCATE", Token.TRUNCATE);
 
         map.put("TRUE", Token.TRUE);
         map.put("FALSE", Token.FALSE);

src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleLexer.java

@@ -85,6 +85,7 @@ public class OracleLexer extends Lexer {
         map.put("LOCK", Token.LOCK);
         map.put("SOME", Token.SOME);
         map.put("ANY", Token.ANY);
+        map.put("TRUNCATE", Token.TRUNCATE);
 
         map.put("START", Token.START);
         map.put("CONNECT", Token.CONNECT);

src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGSQLStatement.java

@@ -0,0 +1,7 @@
+package com.alibaba.druid.sql.dialect.postgresql.ast;
+
+import com.alibaba.druid.sql.ast.SQLStatement;
+
+public interface PGSQLStatement extends SQLStatement, PGSQLObject {
+
+}

src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGSQLStatementImpl.java

@@ -0,0 +1,8 @@
+package com.alibaba.druid.sql.dialect.postgresql.ast;
+
+
+public abstract class PGSQLStatementImpl extends PGSQLObjectImpl implements PGSQLStatement {
+
+    private static final long serialVersionUID = 1L;
+
+}

src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGTruncateStatement.java

@@ -0,0 +1,43 @@
+package com.alibaba.druid.sql.dialect.postgresql.ast;
+
+import com.alibaba.druid.sql.ast.statement.SQLTruncateStatement;
+import com.alibaba.druid.sql.dialect.postgresql.visitor.PGASTVisitor;
+
+public class PGTruncateStatement extends SQLTruncateStatement implements PGSQLStatement{
+
+    private static final long  serialVersionUID = 1L;
+
+    private boolean            only;
+    private Boolean            restartIdentity;
+    private Boolean            cascade;
+
+    public boolean isOnly() {
+        return only;
+    }
+
+    public void setOnly(boolean only) {
+        this.only = only;
+    }
+
+    public Boolean getRestartIdentity() {
+        return restartIdentity;
+    }
+
+    public void setRestartIdentity(Boolean restartIdentity) {
+        this.restartIdentity = restartIdentity;
+    }
+
+    public Boolean getCascade() {
+        return cascade;
+    }
+
+    public void setCascade(Boolean cascade) {
+        this.cascade = cascade;
+    }
+
+    public void accept0(PGASTVisitor visitor) {
+        if (visitor.visit(this)) {
+            acceptChild(visitor, tableNames);
+        }
+    }
+}

src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGLexer.java

@@ -81,6 +81,7 @@ public class PGLexer extends Lexer {
 	        map.put("LOCK", Token.LOCK);
 	        map.put("SOME", Token.SOME);
 	        map.put("ANY", Token.ANY);
+	        map.put("TRUNCATE", Token.TRUNCATE);
 
 	        map.put("LIMIT", Token.LIMIT);
 	        map.put("OFFSET", Token.OFFSET);

src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGSQLStatementParser.java

@@ -2,7 +2,9 @@ package com.alibaba.druid.sql.dialect.postgresql.parser;
 
 import java.util.List;
 
+import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.dialect.postgresql.ast.PGTruncateStatement;
 import com.alibaba.druid.sql.parser.Lexer;
 import com.alibaba.druid.sql.parser.ParserException;
 import com.alibaba.druid.sql.parser.SQLStatementParser;
@@ -22,6 +24,53 @@ public class PGSQLStatementParser extends SQLStatementParser {
 		return new PGSelectParser(this.lexer);
 	}
 	
+    public SQLStatement parseTruncate() {
+        accept(Token.TRUNCATE);
+        
+        PGTruncateStatement stmt = new PGTruncateStatement();
+        
+        if (lexer.token() == Token.TABLE) {
+            lexer.nextToken();
+        }
+        
+        if (lexer.token() == Token.ONLY) {
+            lexer.nextToken();
+            stmt.setOnly(true);
+        }
+        
+        for (;;) {
+            SQLName name = this.exprParser.name();
+            stmt.getTableNames().add(name);
+            
+            if (lexer.token() == Token.COMMA) {
+                lexer.nextToken();
+                continue;
+            }
+            
+            break;
+        }
+        
+        if (lexer.token() == Token.RESTART) {
+            lexer.nextToken();
+            accept(Token.IDENTITY);
+            stmt.setRestartIdentity(Boolean.TRUE);
+        } else if (lexer.token() == Token.SHARE) {
+            lexer.nextToken();
+            accept(Token.IDENTITY);
+            stmt.setRestartIdentity(Boolean.FALSE);
+        }
+        
+        if (lexer.token() == Token.CASCADE) {
+            lexer.nextToken();
+            stmt.setCascade(Boolean.TRUE);
+        } else if (lexer.token() == Token.RESTRICT) {
+            lexer.nextToken();
+            stmt.setCascade(Boolean.FALSE);
+        }
+        
+    	return stmt;
+    }
+	
 	public boolean parseStatementListDialect(List<SQLStatement> statementList) {
 		if (lexer.token() == Token.WITH) {
 			SQLStatement stmt = parseSelect();

src/main/java/com/alibaba/druid/sql/dialect/postgresql/visitor/PGASTVisitor.java

@@ -1,30 +1,36 @@
 package com.alibaba.druid.sql.dialect.postgresql.visitor;
 
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock;
+import com.alibaba.druid.sql.dialect.postgresql.ast.PGTruncateStatement;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
 public interface PGASTVisitor extends SQLASTVisitor {
-	void endVisit(PGSelectQueryBlock.WindowClause x);
 
-	boolean visit(PGSelectQueryBlock.WindowClause x);
+    void endVisit(PGSelectQueryBlock.WindowClause x);
 
-	void endVisit(PGSelectQueryBlock.FetchClause x);
+    boolean visit(PGSelectQueryBlock.WindowClause x);
 
-	boolean visit(PGSelectQueryBlock.FetchClause x);
+    void endVisit(PGSelectQueryBlock.FetchClause x);
 
-	void endVisit(PGSelectQueryBlock.ForClause x);
+    boolean visit(PGSelectQueryBlock.FetchClause x);
 
-	boolean visit(PGSelectQueryBlock.ForClause x);
-	
-	void endVisit(PGSelectQueryBlock.WithQuery x);
-	
-	boolean visit(PGSelectQueryBlock.WithQuery x);
-	
-	void endVisit(PGSelectQueryBlock.WithClause x);
-	
-	boolean visit(PGSelectQueryBlock.WithClause x);
-	
-	void endVisit(PGSelectQueryBlock.IntoClause x);
-	
-	boolean visit(PGSelectQueryBlock.IntoClause x);
+    void endVisit(PGSelectQueryBlock.ForClause x);
+
+    boolean visit(PGSelectQueryBlock.ForClause x);
+
+    void endVisit(PGSelectQueryBlock.WithQuery x);
+
+    boolean visit(PGSelectQueryBlock.WithQuery x);
+
+    void endVisit(PGSelectQueryBlock.WithClause x);
+
+    boolean visit(PGSelectQueryBlock.WithClause x);
+
+    void endVisit(PGSelectQueryBlock.IntoClause x);
+
+    boolean visit(PGSelectQueryBlock.IntoClause x);
+
+    void endVisit(PGTruncateStatement x);
+
+    boolean visit(PGTruncateStatement x);
 }

src/main/java/com/alibaba/druid/sql/dialect/postgresql/visitor/PGASTVisitorAdapter.java

@@ -6,75 +6,86 @@ import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.IntoClaus
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.WindowClause;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.WithClause;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.WithQuery;
+import com.alibaba.druid.sql.dialect.postgresql.ast.PGTruncateStatement;
 import com.alibaba.druid.sql.visitor.SQLASTVisitorAdapter;
 
-public class PGASTVisitorAdapter extends SQLASTVisitorAdapter implements
-		PGASTVisitor {
+public class PGASTVisitorAdapter extends SQLASTVisitorAdapter implements PGASTVisitor {
 
-	@Override
-	public void endVisit(WindowClause x) {
+    @Override
+    public void endVisit(WindowClause x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(WindowClause x) {
+    @Override
+    public boolean visit(WindowClause x) {
 
-		return true;
-	}
+        return true;
+    }
 
-	@Override
-	public void endVisit(FetchClause x) {
+    @Override
+    public void endVisit(FetchClause x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(FetchClause x) {
+    @Override
+    public boolean visit(FetchClause x) {
 
-		return true;
-	}
+        return true;
+    }
 
-	@Override
-	public void endVisit(ForClause x) {
+    @Override
+    public void endVisit(ForClause x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(ForClause x) {
+    @Override
+    public boolean visit(ForClause x) {
 
-		return true;
-	}
+        return true;
+    }
 
-	@Override
-	public void endVisit(WithQuery x) {
+    @Override
+    public void endVisit(WithQuery x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(WithQuery x) {
+    @Override
+    public boolean visit(WithQuery x) {
 
-		return true;
-	}
+        return true;
+    }
 
-	@Override
-	public void endVisit(WithClause x) {
+    @Override
+    public void endVisit(WithClause x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(WithClause x) {
+    @Override
+    public boolean visit(WithClause x) {
 
-		return true;
-	}
-	
-	@Override
-	public void endVisit(IntoClause x) {
-		
-	}
-	
-	@Override
-	public boolean visit(IntoClause x) {
-		
-		return true;
-	}
+        return true;
+    }
+
+    @Override
+    public void endVisit(IntoClause x) {
+
+    }
+
+    @Override
+    public boolean visit(IntoClause x) {
+
+        return true;
+    }
+
+    @Override
+    public void endVisit(PGTruncateStatement x) {
+
+    }
+
+    @Override
+    public boolean visit(PGTruncateStatement x) {
+
+        return true;
+    }
 
 }

src/main/java/com/alibaba/druid/sql/dialect/postgresql/visitor/PGOutputVisitor.java

@@ -9,6 +9,7 @@ import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.IntoClaus
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.WindowClause;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.WithClause;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.WithQuery;
+import com.alibaba.druid.sql.dialect.postgresql.ast.PGTruncateStatement;
 import com.alibaba.druid.sql.visitor.SQLASTOutputVisitor;
 
 public class PGOutputVisitor extends SQLASTOutputVisitor implements
@@ -232,4 +233,36 @@ public class PGOutputVisitor extends SQLASTOutputVisitor implements
 		x.getTable().accept(this);
 		return false;
 	}
+	
+	@Override
+	public void endVisit(PGTruncateStatement x) {
+	    
+	}
+	
+	@Override
+	public boolean visit(PGTruncateStatement x) {
+	    print("TRUNCATE TABLE ");
+	    if (x.isOnly()) {
+	        print("ONLY ");
+	    }
+	    
+	    printlnAndAccept(x.getTableNames(), ", ");
+	    
+	    if (x.getRestartIdentity() != null) {
+	        if (x.getRestartIdentity().booleanValue()) {
+	            print(" RESTART IDENTITY");
+	        } else {
+	            print(" CONTINUE IDENTITY");
+	        }
+	    }
+	    
+	    if (x.getCascade() != null) {
+            if (x.getCascade().booleanValue()) {
+                print(" CASCADE");
+            } else {
+                print(" RESTRICT");
+            }
+        }
+	    return false;
+	}
 }

src/main/java/com/alibaba/druid/sql/dialect/postgresql/visitor/PGSchemaStatVisitor.java

@@ -1,86 +1,97 @@
 package com.alibaba.druid.sql.dialect.postgresql.visitor;
 
+import com.alibaba.druid.sql.ast.statement.SQLTruncateStatement;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.FetchClause;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.ForClause;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.IntoClause;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.WindowClause;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.WithClause;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGSelectQueryBlock.WithQuery;
+import com.alibaba.druid.sql.dialect.postgresql.ast.PGTruncateStatement;
 import com.alibaba.druid.sql.visitor.SchemaStatVisitor;
 import com.alibaba.druid.stat.TableStat;
 
-public class PGSchemaStatVisitor extends SchemaStatVisitor implements
-		PGASTVisitor {
+public class PGSchemaStatVisitor extends SchemaStatVisitor implements PGASTVisitor {
 
-	@Override
-	public void endVisit(WindowClause x) {
+    @Override
+    public void endVisit(WindowClause x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(WindowClause x) {
-		return true;
-	}
+    @Override
+    public boolean visit(WindowClause x) {
+        return true;
+    }
 
-	@Override
-	public void endVisit(FetchClause x) {
+    @Override
+    public void endVisit(FetchClause x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(FetchClause x) {
-		return true;
-	}
+    @Override
+    public boolean visit(FetchClause x) {
+        return true;
+    }
 
-	@Override
-	public void endVisit(ForClause x) {
+    @Override
+    public void endVisit(ForClause x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(ForClause x) {
+    @Override
+    public boolean visit(ForClause x) {
 
-		return true;
-	}
+        return true;
+    }
 
-	@Override
-	public void endVisit(WithQuery x) {
+    @Override
+    public void endVisit(WithQuery x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(WithQuery x) {
+    @Override
+    public boolean visit(WithQuery x) {
 
-		return true;
-	}
+        return true;
+    }
 
-	@Override
-	public void endVisit(WithClause x) {
+    @Override
+    public void endVisit(WithClause x) {
 
-	}
+    }
 
-	@Override
-	public boolean visit(WithClause x) {
+    @Override
+    public boolean visit(WithClause x) {
 
-		return true;
-	}
+        return true;
+    }
 
-	@Override
-	public void endVisit(IntoClause x) {
-		
-	}
+    @Override
+    public void endVisit(IntoClause x) {
 
-	@Override
-	public boolean visit(IntoClause x) {
-		String ident = x.getTable().toString();
-		
-		TableStat stat = tableStats.get(ident);
-		if (stat == null) {
-			stat = new TableStat();
-			tableStats.put(new TableStat.Name(ident), stat);
-		}
-		stat.incrementInsertCount();
-		return false;
-	}
+    }
 
+    @Override
+    public boolean visit(IntoClause x) {
+        String ident = x.getTable().toString();
+
+        TableStat stat = tableStats.get(ident);
+        if (stat == null) {
+            stat = new TableStat();
+            tableStats.put(new TableStat.Name(ident), stat);
+        }
+        stat.incrementInsertCount();
+        return false;
+    }
+
+    @Override
+    public void endVisit(PGTruncateStatement x) {
+
+    }
+
+    @Override
+    public boolean visit(PGTruncateStatement x) {
+        this.visit((SQLTruncateStatement) x);
+        return false;
+    }
 }

src/main/java/com/alibaba/druid/sql/parser/SQLStatementParser.java

@@ -116,6 +116,12 @@ public class SQLStatementParser extends SQLParser {
                     continue;
                 }
             }
+            
+            if (lexer.token() == Token.TRUNCATE) {
+                SQLStatement stmt = parseTruncate();
+                statementList.add(stmt);
+                continue;
+            }
 
             if (identifierEquals("CALL")) {
                 SQLCallStatement stmt = parseCall();
@@ -130,6 +136,10 @@ public class SQLStatementParser extends SQLParser {
             throw new ParserException("TODO " + lexer.token());
         }
     }
+    
+    public SQLStatement parseTruncate() {
+    	throw new ParserException("TODO " + lexer.token());
+    }
 
     public SQLStatement parseInsert() {
         accept(Token.INSERT);

src/main/java/com/alibaba/druid/sql/parser/Token.java

@@ -92,6 +92,7 @@ public enum Token {
     LOCK("LOCK"), 
     SOME("SOME"), 
     ANY("ANY"),
+    TRUNCATE("TRUNCATE"),
 
     // mysql
     TRUE("TRUE"), 
@@ -115,6 +116,11 @@ public enum Token {
     TEMPORARY("TEMPORARY"),
     TEMP("TEMP"),
     UNLOGGED("UNLOGGED"),
+    RESTART("RESTART"),
+    IDENTITY("IDENTITY"),
+    CONTINUE("CONTINUE"),
+    CASCADE("CASCADE"),
+    RESTRICT("RESTRICT"),
     
     // oracle
     START("START"),

src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java

@@ -73,6 +73,7 @@ import com.alibaba.druid.sql.ast.statement.SQLSelectStatement;
 import com.alibaba.druid.sql.ast.statement.SQLSetStatement;
 import com.alibaba.druid.sql.ast.statement.SQLSubqueryTableSource;
 import com.alibaba.druid.sql.ast.statement.SQLTableElement;
+import com.alibaba.druid.sql.ast.statement.SQLTruncateStatement;
 import com.alibaba.druid.sql.ast.statement.SQLUnionQuery;
 import com.alibaba.druid.sql.ast.statement.SQLUniqueConstraint;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateSetItem;
@@ -864,4 +865,16 @@ public class SQLASTOutputVisitor extends SQLASTVisitorAdapter {
 
         return false;
     }
+    
+    @Override
+    public void endVisit(SQLTruncateStatement x) {
+        
+    }
+    
+    @Override
+    public boolean visit(SQLTruncateStatement x) {
+        print("TRUNCATE TABLE ");
+        printAndAccept(x.getTableNames(), ", ");
+        return false;
+    }
 }

src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitor.java

@@ -68,6 +68,7 @@ import com.alibaba.druid.sql.ast.statement.SQLSelectStatement;
 import com.alibaba.druid.sql.ast.statement.SQLSetStatement;
 import com.alibaba.druid.sql.ast.statement.SQLSubqueryTableSource;
 import com.alibaba.druid.sql.ast.statement.SQLTableElement;
+import com.alibaba.druid.sql.ast.statement.SQLTruncateStatement;
 import com.alibaba.druid.sql.ast.statement.SQLUnionQuery;
 import com.alibaba.druid.sql.ast.statement.SQLUniqueConstraint;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateSetItem;
@@ -314,4 +315,8 @@ public interface SQLASTVisitor {
     void endVisit(SQLSubqueryTableSource x);
 
     boolean visit(SQLSubqueryTableSource x);
+    
+    void endVisit(SQLTruncateStatement x);
+    
+    boolean visit(SQLTruncateStatement x);
 }

src/main/java/com/alibaba/druid/sql/visitor/SQLASTVisitorAdapter.java

@@ -69,6 +69,7 @@ import com.alibaba.druid.sql.ast.statement.SQLSelectStatement;
 import com.alibaba.druid.sql.ast.statement.SQLSetStatement;
 import com.alibaba.druid.sql.ast.statement.SQLSubqueryTableSource;
 import com.alibaba.druid.sql.ast.statement.SQLTableElement;
+import com.alibaba.druid.sql.ast.statement.SQLTruncateStatement;
 import com.alibaba.druid.sql.ast.statement.SQLUnionQuery;
 import com.alibaba.druid.sql.ast.statement.SQLUniqueConstraint;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateSetItem;
@@ -539,4 +540,14 @@ public class SQLASTVisitorAdapter implements SQLASTVisitor {
     public boolean visit(SQLSubqueryTableSource x) {
         return true;
     }
+    
+    @Override
+    public void endVisit(SQLTruncateStatement x) {
+        
+    }
+    
+    @Override
+    public boolean visit(SQLTruncateStatement x) {
+        return true;
+    }
 }

src/main/java/com/alibaba/druid/sql/visitor/SchemaStatVisitor.java

@@ -21,266 +21,298 @@ import com.alibaba.druid.sql.ast.statement.SQLSelect;
 import com.alibaba.druid.sql.ast.statement.SQLSelectQueryBlock;
 import com.alibaba.druid.sql.ast.statement.SQLSelectStatement;
 import com.alibaba.druid.sql.ast.statement.SQLSubqueryTableSource;
+import com.alibaba.druid.sql.ast.statement.SQLTruncateStatement;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateStatement;
 import com.alibaba.druid.stat.TableStat;
 import com.alibaba.druid.stat.TableStat.Column;
 import com.alibaba.druid.stat.TableStat.Mode;
 
 public class SchemaStatVisitor extends SQLASTVisitorAdapter {
-	protected HashMap<TableStat.Name, TableStat> tableStats = new HashMap<TableStat.Name, TableStat>();
-	protected Set<Column> fields = new HashSet<Column>();
 
-	protected final static ThreadLocal<Map<String, String>> aliasLocal = new ThreadLocal<Map<String, String>>();
-	protected final static ThreadLocal<String> currentTableLocal = new ThreadLocal<String>();
-	protected final static ThreadLocal<Mode> modeLocal = new ThreadLocal<Mode>();
+    protected HashMap<TableStat.Name, TableStat>            tableStats        = new HashMap<TableStat.Name, TableStat>();
+    protected Set<Column>                                   fields            = new HashSet<Column>();
 
-	@Override
-	public boolean visit(SQLInsertStatement x) {
-		x.putAttribute("_original_use_mode", modeLocal.get());
-		modeLocal.set(Mode.Insert);
+    protected final static ThreadLocal<Map<String, String>> aliasLocal        = new ThreadLocal<Map<String, String>>();
+    protected final static ThreadLocal<String>              currentTableLocal = new ThreadLocal<String>();
+    protected final static ThreadLocal<Mode>                modeLocal         = new ThreadLocal<Mode>();
 
-		aliasLocal.set(new HashMap<String, String>());
+    @Override
+    public boolean visit(SQLTruncateStatement x) {
+        x.putAttribute("_original_use_mode", modeLocal.get());
+        modeLocal.set(Mode.Insert);
 
-		String originalTable = currentTableLocal.get();
+        aliasLocal.set(new HashMap<String, String>());
 
-		if (x.getTableName() instanceof SQLName) {
-			String ident = ((SQLName) x.getTableName()).toString();
-			currentTableLocal.set(ident);
-			x.putAttribute("_old_local_", originalTable);
+        String originalTable = currentTableLocal.get();
 
-			TableStat stat = tableStats.get(ident);
-			if (stat == null) {
-				stat = new TableStat();
-				tableStats.put(new TableStat.Name(ident), stat);
-			}
-			stat.incrementInsertCount();
+        for (SQLName name : x.getTableNames()) {
+            String ident = name.toString();
+            currentTableLocal.set(ident);
+            x.putAttribute("_old_local_", originalTable);
 
-			Map<String, String> aliasMap = aliasLocal.get();
-			if (aliasMap != null) {
-				if (x.getAlias() != null) {
-					aliasMap.put(x.getAlias(), ident);
-				}
-				aliasMap.put(ident, ident);
-			}
-		}
+            TableStat stat = tableStats.get(ident);
+            if (stat == null) {
+                stat = new TableStat();
+                tableStats.put(new TableStat.Name(ident), stat);
+            }
+            stat.incrementInsertCount();
 
-		accept(x.getColumns());
-		accept(x.getQuery());
+            Map<String, String> aliasMap = aliasLocal.get();
+            if (aliasMap != null) {
+                aliasMap.put(ident, ident);
+            }
+        }
 
-		return false;
-	}
+        return false;
+    }
 
-	protected void accept(SQLObject x) {
-		if (x != null) {
-			x.accept(this);
-		}
-	}
+    @Override
+    public boolean visit(SQLInsertStatement x) {
+        x.putAttribute("_original_use_mode", modeLocal.get());
+        modeLocal.set(Mode.Insert);
 
-	protected void accept(List<? extends SQLObject> nodes) {
-		for (int i = 0, size = nodes.size(); i < size; ++i) {
-			accept(nodes.get(i));
-		}
-	}
+        aliasLocal.set(new HashMap<String, String>());
 
-	public boolean visit(SQLSelectQueryBlock x) {
+        String originalTable = currentTableLocal.get();
 
-		if (x.getFrom() instanceof SQLSubqueryTableSource) {
-			x.getFrom().accept(this);
-			return false;
-		}
+        if (x.getTableName() instanceof SQLName) {
+            String ident = ((SQLName) x.getTableName()).toString();
+            currentTableLocal.set(ident);
+            x.putAttribute("_old_local_", originalTable);
 
-		x.putAttribute("_original_use_mode", modeLocal.get());
-		modeLocal.set(Mode.Select);
+            TableStat stat = tableStats.get(ident);
+            if (stat == null) {
+                stat = new TableStat();
+                tableStats.put(new TableStat.Name(ident), stat);
+            }
+            stat.incrementInsertCount();
 
-		String originalTable = currentTableLocal.get();
+            Map<String, String> aliasMap = aliasLocal.get();
+            if (aliasMap != null) {
+                if (x.getAlias() != null) {
+                    aliasMap.put(x.getAlias(), ident);
+                }
+                aliasMap.put(ident, ident);
+            }
+        }
 
-		if (x.getFrom() instanceof SQLExprTableSource) {
-			SQLExprTableSource tableSource = (SQLExprTableSource) x.getFrom();
-			if (tableSource.getExpr() instanceof SQLName) {
-				String ident = tableSource.getExpr().toString();
-				currentTableLocal.set(ident);
-				x.putAttribute("_old_local_", originalTable);
-			}
-		}
+        accept(x.getColumns());
+        accept(x.getQuery());
 
-		x.getFrom().accept(this); // 提前执行，获得aliasMap
+        return false;
+    }
 
-		return true;
-	}
+    protected void accept(SQLObject x) {
+        if (x != null) {
+            x.accept(this);
+        }
+    }
 
-	public void endVisit(SQLSelectQueryBlock x) {
-		String originalTable = (String) x.getAttribute("_old_local_");
-		x.putAttribute("table", currentTableLocal.get());
-		currentTableLocal.set(originalTable);
+    protected void accept(List<? extends SQLObject> nodes) {
+        for (int i = 0, size = nodes.size(); i < size; ++i) {
+            accept(nodes.get(i));
+        }
+    }
 
-		Mode originalMode = (Mode) x.getAttribute("_original_use_mode");
-		modeLocal.set(originalMode);
-	}
+    public boolean visit(SQLSelectQueryBlock x) {
 
-	public boolean visit(SQLJoinTableSource x) {
-		return true;
-	}
+        if (x.getFrom() instanceof SQLSubqueryTableSource) {
+            x.getFrom().accept(this);
+            return false;
+        }
 
-	public boolean visit(SQLPropertyExpr x) {
-		if (x.getOwner() instanceof SQLIdentifierExpr) {
-			String owner = ((SQLIdentifierExpr) x.getOwner()).getName();
+        x.putAttribute("_original_use_mode", modeLocal.get());
+        modeLocal.set(Mode.Select);
 
-			if (owner != null) {
-				Map<String, String> aliasMap = aliasLocal.get();
-				if (aliasMap != null) {
-					String table = aliasMap.get(owner);
+        String originalTable = currentTableLocal.get();
 
-					// table == null时是SubQuery
-					if (table != null) {
-						fields.add(new Column(table, x.getName()));
-					}
-				}
-			}
-		}
-		return false;
-	}
+        if (x.getFrom() instanceof SQLExprTableSource) {
+            SQLExprTableSource tableSource = (SQLExprTableSource) x.getFrom();
+            if (tableSource.getExpr() instanceof SQLName) {
+                String ident = tableSource.getExpr().toString();
+                currentTableLocal.set(ident);
+                x.putAttribute("_old_local_", originalTable);
+            }
+        }
 
-	public boolean visit(SQLIdentifierExpr x) {
-		String currentTable = currentTableLocal.get();
+        x.getFrom().accept(this); // 提前执行，获得aliasMap
 
-		if (currentTable != null) {
-			fields.add(new Column(currentTable, x.getName()));
-		}
-		return false;
-	}
+        return true;
+    }
 
-	public boolean visit(SQLAllColumnExpr x) {
-		String currentTable = currentTableLocal.get();
+    public void endVisit(SQLSelectQueryBlock x) {
+        String originalTable = (String) x.getAttribute("_old_local_");
+        x.putAttribute("table", currentTableLocal.get());
+        currentTableLocal.set(originalTable);
 
-		if (currentTable != null) {
-			fields.add(new Column(currentTable, "*"));
-		}
-		return false;
-	}
+        Mode originalMode = (Mode) x.getAttribute("_original_use_mode");
+        modeLocal.set(originalMode);
+    }
 
-	public Map<TableStat.Name, TableStat> getTables() {
-		return tableStats;
-	}
+    public boolean visit(SQLJoinTableSource x) {
+        return true;
+    }
 
-	public boolean containsTable(String tableName) {
-		return tableStats.containsKey(new TableStat.Name(tableName));
-	}
+    public boolean visit(SQLPropertyExpr x) {
+        if (x.getOwner() instanceof SQLIdentifierExpr) {
+            String owner = ((SQLIdentifierExpr) x.getOwner()).getName();
 
-	public Set<Column> getFields() {
-		return fields;
-	}
+            if (owner != null) {
+                Map<String, String> aliasMap = aliasLocal.get();
+                if (aliasMap != null) {
+                    String table = aliasMap.get(owner);
 
-	public boolean visit(SQLSelectStatement x) {
-		aliasLocal.set(new HashMap<String, String>());
-		return true;
-	}
+                    // table == null时是SubQuery
+                    if (table != null) {
+                        fields.add(new Column(table, x.getName()));
+                    }
+                }
+            }
+        }
+        return false;
+    }
 
-	public void endVisit(SQLSelectStatement x) {
-		aliasLocal.set(null);
-	}
+    public boolean visit(SQLIdentifierExpr x) {
+        String currentTable = currentTableLocal.get();
 
-	public boolean visit(SQLSubqueryTableSource x) {
-		Map<String, String> aliasMap = aliasLocal.get();
-		if (aliasMap != null) {
-			if (x.getAlias() != null) {
-				aliasMap.put(x.getAlias(), null);
-			}
-		}
-		return true;
-	}
+        if (currentTable != null) {
+            fields.add(new Column(currentTable, x.getName()));
+        }
+        return false;
+    }
 
-	protected boolean isSimpleExprTableSource(SQLExprTableSource x) {
-		return x.getExpr() instanceof SQLName;
-	}
+    public boolean visit(SQLAllColumnExpr x) {
+        String currentTable = currentTableLocal.get();
 
-	public boolean visit(SQLExprTableSource x) {
-		if (isSimpleExprTableSource(x)) {
-			String ident = x.getExpr().toString();
-			TableStat stat = tableStats.get(ident);
-			if (stat == null) {
-				stat = new TableStat();
-				tableStats.put(new TableStat.Name(ident), stat);
-			}
+        if (currentTable != null) {
+            fields.add(new Column(currentTable, "*"));
+        }
+        return false;
+    }
 
-			Mode mode = modeLocal.get();
-			switch (mode) {
-			case Delete:
-				stat.incrementDeleteCount();
-				break;
-			case Insert:
-				stat.incrementInsertCount();
-				break;
-			case Update:
-				stat.incrementUpdateCount();
-				break;
-			case Select:
-				stat.incrementSelectCount();
-				break;
-			default:
-				break;
-			}
+    public Map<TableStat.Name, TableStat> getTables() {
+        return tableStats;
+    }
 
-			Map<String, String> aliasMap = aliasLocal.get();
-			if (aliasMap != null) {
-				if (x.getAlias() != null) {
-					aliasMap.put(x.getAlias(), ident);
-				}
-				aliasMap.put(ident, ident);
-			}
-		} else {
-			accept(x.getExpr());
-		}
+    public boolean containsTable(String tableName) {
+        return tableStats.containsKey(new TableStat.Name(tableName));
+    }
 
-		return false;
-	}
+    public Set<Column> getFields() {
+        return fields;
+    }
 
-	public boolean visit(SQLSelect x) {
-		accept(x.getQuery());
+    public boolean visit(SQLSelectStatement x) {
+        aliasLocal.set(new HashMap<String, String>());
+        return true;
+    }
 
-		String originalTable = currentTableLocal.get();
+    public void endVisit(SQLSelectStatement x) {
+        aliasLocal.set(null);
+    }
 
-		currentTableLocal.set((String) x.getQuery().getAttribute("table"));
-		x.putAttribute("_old_local_", originalTable);
+    public boolean visit(SQLSubqueryTableSource x) {
+        Map<String, String> aliasMap = aliasLocal.get();
+        if (aliasMap != null) {
+            if (x.getAlias() != null) {
+                aliasMap.put(x.getAlias(), null);
+            }
+        }
+        return true;
+    }
 
-		accept(x.getOrderBy());
+    protected boolean isSimpleExprTableSource(SQLExprTableSource x) {
+        return x.getExpr() instanceof SQLName;
+    }
 
-		currentTableLocal.set(originalTable);
+    public boolean visit(SQLExprTableSource x) {
+        if (isSimpleExprTableSource(x)) {
+            String ident = x.getExpr().toString();
+            TableStat stat = tableStats.get(ident);
+            if (stat == null) {
+                stat = new TableStat();
+                tableStats.put(new TableStat.Name(ident), stat);
+            }
 
-		return false;
-	}
+            Mode mode = modeLocal.get();
+            switch (mode) {
+                case Delete:
+                    stat.incrementDeleteCount();
+                    break;
+                case Insert:
+                    stat.incrementInsertCount();
+                    break;
+                case Update:
+                    stat.incrementUpdateCount();
+                    break;
+                case Select:
+                    stat.incrementSelectCount();
+                    break;
+                default:
+                    break;
+            }
 
-	public boolean visit(SQLAggregateExpr x) {
-		accept(x.getArguments());
-		return false;
-	}
+            Map<String, String> aliasMap = aliasLocal.get();
+            if (aliasMap != null) {
+                if (x.getAlias() != null) {
+                    aliasMap.put(x.getAlias(), ident);
+                }
+                aliasMap.put(ident, ident);
+            }
+        } else {
+            accept(x.getExpr());
+        }
 
-	public boolean visit(SQLMethodInvokeExpr x) {
-		accept(x.getParameters());
-		return false;
-	}
+        return false;
+    }
 
-	public boolean visit(SQLUpdateStatement x) {
-		aliasLocal.set(new HashMap<String, String>());
+    public boolean visit(SQLSelect x) {
+        accept(x.getQuery());
 
-		String ident = x.getTableName().toString();
-		currentTableLocal.set(ident);
+        String originalTable = currentTableLocal.get();
 
-		TableStat stat = tableStats.get(ident);
-		if (stat == null) {
-			stat = new TableStat();
-			tableStats.put(new TableStat.Name(ident), stat);
-		}
-		stat.incrementUpdateCount();
+        currentTableLocal.set((String) x.getQuery().getAttribute("table"));
+        x.putAttribute("_old_local_", originalTable);
 
-		Map<String, String> aliasMap = aliasLocal.get();
-		aliasMap.put(ident, ident);
+        accept(x.getOrderBy());
 
-		accept(x.getItems());
-		accept(x.getWhere());
+        currentTableLocal.set(originalTable);
+
+        return false;
+    }
+
+    public boolean visit(SQLAggregateExpr x) {
+        accept(x.getArguments());
+        return false;
+    }
+
+    public boolean visit(SQLMethodInvokeExpr x) {
+        accept(x.getParameters());
+        return false;
+    }
+
+    public boolean visit(SQLUpdateStatement x) {
+        aliasLocal.set(new HashMap<String, String>());
+
+        String ident = x.getTableName().toString();
+        currentTableLocal.set(ident);
+
+        TableStat stat = tableStats.get(ident);
+        if (stat == null) {
+            stat = new TableStat();
+            tableStats.put(new TableStat.Name(ident), stat);
+        }
+        stat.incrementUpdateCount();
+
+        Map<String, String> aliasMap = aliasLocal.get();
+        aliasMap.put(ident, ident);
+
+        accept(x.getItems());
+        accept(x.getWhere());
+
+        return false;
+    }
 
-		return false;
-	}
-	
     public boolean visit(SQLDeleteStatement x) {
         aliasLocal.set(new HashMap<String, String>());
 
@@ -308,7 +340,7 @@ public class SchemaStatVisitor extends SQLASTVisitorAdapter {
         aliasLocal.set(null);
     }
 
-	public void endVisit(SQLUpdateStatement x) {
-		aliasLocal.set(null);
-	}
+    public void endVisit(SQLUpdateStatement x) {
+        aliasLocal.set(null);
+    }
 }