improved sql parser.

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

@@ -17,6 +17,8 @@ package com.alibaba.druid.sql.ast.statement;
 
 import com.alibaba.druid.sql.ast.SQLCommentHint;
 import com.alibaba.druid.sql.ast.SQLDataTypeImpl;
+import com.alibaba.druid.sql.ast.SQLExpr;
+import com.alibaba.druid.sql.ast.expr.SQLIntegerExpr;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
 import java.util.List;
@@ -78,6 +80,17 @@ public class SQLCharacterDataType extends SQLDataTypeImpl {
         this.hints = hints;
     }
 
+    public int getLength() {
+        if (this.arguments.size() == 1) {
+            SQLExpr arg = this.arguments.get(0);
+            if (arg instanceof SQLIntegerExpr) {
+                return ((SQLIntegerExpr) arg).getNumber().intValue();
+            }
+        }
+
+        return -1;
+    }
+
     @Override
     protected void accept0(SQLASTVisitor visitor) {
         if (visitor.visit(this)) {

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

@@ -20,6 +20,7 @@ import java.util.HashMap;
 import java.util.List;
 
 import com.alibaba.druid.sql.SQLUtils;
+import com.alibaba.druid.sql.ast.SQLDataType;
 import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.SQLStatementImpl;
@@ -27,6 +28,7 @@ import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
 import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlTableIndex;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 import com.alibaba.druid.stat.TableStat;
+import com.alibaba.druid.util.lang.Consumer;
 
 public class SQLCreateTableStatement extends SQLStatementImpl implements SQLDDLStatement {
 
@@ -213,4 +215,16 @@ public class SQLCreateTableStatement extends SQLStatementImpl implements SQLDDLS
 
         return null;
     }
+
+    public void forEachColumn(Consumer<SQLColumnDefinition> columnConsumer) {
+        if (columnConsumer == null) {
+            return;
+        }
+
+        for (SQLTableElement element : this.tableElementList) {
+            if (element instanceof SQLColumnDefinition) {
+                columnConsumer.accept((SQLColumnDefinition) element);
+            }
+        }
+    }
 }

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

@@ -157,4 +157,28 @@ public class SQLSelectItem extends SQLObjectImpl implements SQLReplaceable {
 
         return false;
     }
+
+    public boolean match(String alias) {
+        if (alias == null) {
+            return false;
+        }
+
+        String alias_normalized = SQLUtils.normalize(alias);
+
+        if (alias_normalized.equalsIgnoreCase(this.alias)) {
+            return true;
+        }
+
+        if (expr instanceof SQLIdentifierExpr) {
+            String ident = ((SQLIdentifierExpr) expr).getName();
+            return alias_normalized.equalsIgnoreCase(SQLUtils.normalize(ident));
+        }
+
+        if (expr instanceof SQLPropertyExpr) {
+            String ident = ((SQLPropertyExpr) expr).getName();
+            return alias_normalized.equalsIgnoreCase(SQLUtils.normalize(ident));
+        }
+
+        return false;
+    }
 }

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

@@ -18,7 +18,9 @@ package com.alibaba.druid.sql.ast.statement;
 import java.util.ArrayList;
 import java.util.List;
 
+import com.alibaba.druid.sql.SQLUtils;
 import com.alibaba.druid.sql.ast.*;
+import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
 public class SQLSelectQueryBlock extends SQLObjectImpl implements SQLSelectQuery, SQLReplaceable {
@@ -421,4 +423,20 @@ public class SQLSelectQueryBlock extends SQLObjectImpl implements SQLSelectQuery
         }
         return false;
     }
+
+    public SQLSelectItem findSelectItem(String ident) {
+        if (ident == null) {
+            return null;
+        }
+
+        String ident_normalized = SQLUtils.normalize(ident);
+
+        for (SQLSelectItem item : this.selectList) {
+            if (item.match(ident_normalized)) {
+                return item;
+            }
+        }
+
+        return null;
+    }
 }

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

@@ -982,7 +982,7 @@ public class OracleExprParser extends SQLExprParser {
             rightExp = equalityRest(rightExp);
 
             expr = new SQLBinaryOpExpr(expr, SQLBinaryOperator.Equality, rightExp, getDbType());
-        } else if (lexer.token() == Token.BANGEQ) {
+        } else if (lexer.token() == Token.BANGEQ || lexer.token() == Token.CARETEQ) {
             lexer.nextToken();
             rightExp = shift();
 

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

@@ -582,7 +582,12 @@ public class Lexer {
                 break;
             case '^':
                 scanChar();
-                token = Token.CARET;
+                if (ch == '=') {
+                    scanChar();
+                    token = Token.CARETEQ;
+                } else {
+                    token = Token.CARET;
+                }
                 break;
             case '%':
                 scanChar();

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

@@ -334,7 +334,8 @@ public enum Token {
     SLASH("/"), 
     AMP("&"), 
     BAR("|"), 
-    CARET("^"), 
+    CARET("^"),
+    CARETEQ("^="),
     PERCENT("%"), 
     LTLT("<<"), 
     GTGT(">>"),

src/main/java/com/alibaba/druid/util/MySqlUtils.java

@@ -29,6 +29,8 @@ import java.sql.Connection;
 import java.sql.Driver;
 import java.sql.SQLException;
 import java.sql.SQLFeatureNotSupportedException;
+import java.util.HashSet;
+import java.util.Set;
 
 public class MySqlUtils {
     static Class<?> utilClass;
@@ -104,4 +106,24 @@ public class MySqlUtils {
         }
         return null;
     }
+
+    private static Set<String> keywords;
+
+    public static boolean isKeyword(String name) {
+        if (name == null) {
+            return false;
+        }
+
+        String name_lower = name.toLowerCase();
+
+        Set<String> words = keywords;
+
+        if (words == null) {
+            words = new HashSet<String>();
+            Utils.loadFromFile("META-INF/druid/parser/mysql/keywords", words);
+            keywords = words;
+        }
+
+        return words.contains(name_lower);
+    }
 }

src/main/java/com/alibaba/druid/util/OracleUtils.java

@@ -15,10 +15,8 @@
  */
 package com.alibaba.druid.util;
 
-import java.sql.Connection;
-import java.sql.PreparedStatement;
-import java.sql.ResultSet;
-import java.sql.SQLException;
+import java.sql.*;
+import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.Set;
 
@@ -28,6 +26,7 @@ import javax.transaction.xa.XAException;
 import oracle.jdbc.OracleConnection;
 import oracle.jdbc.OracleResultSet;
 import oracle.jdbc.OracleStatement;
+import oracle.jdbc.driver.DatabaseError;
 import oracle.jdbc.internal.OraclePreparedStatement;
 import oracle.jdbc.xa.client.OracleXAConnection;
 import oracle.sql.ROWID;
@@ -203,4 +202,24 @@ public class OracleUtils {
 
         return tables.contains(table_lower);
     }
+
+    private static Set<String> keywords;
+
+    public static boolean isKeyword(String name) {
+        if (name == null) {
+            return false;
+        }
+
+        String name_lower = name.toLowerCase();
+
+        Set<String> words = keywords;
+
+        if (words == null) {
+            words = new HashSet<String>();
+            Utils.loadFromFile("META-INF/druid/parser/oracle/keywords", words);
+            keywords = words;
+        }
+
+        return words.contains(name_lower);
+    }
 }

src/main/java/com/alibaba/druid/util/lang/Consumer.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright 1999-2017 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.druid.util.lang;
+
+/**
+ * Created by wenshao on 20/06/2017.
+ */
+public interface Consumer<T> {
+    void accept(T t);
+}