odps support mysql quote, fixed issue #1292

src/main/java/com/alibaba/druid/sql/PagerUtils.java

@@ -30,6 +30,7 @@ import com.alibaba.druid.sql.ast.expr.SQLBinaryOperator;
 import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
 import com.alibaba.druid.sql.ast.expr.SQLIntegerExpr;
 import com.alibaba.druid.sql.ast.expr.SQLNumberExpr;
+import com.alibaba.druid.sql.ast.expr.SQLNumericLiteralExpr;
 import com.alibaba.druid.sql.ast.expr.SQLPropertyExpr;
 import com.alibaba.druid.sql.ast.statement.SQLSelect;
 import com.alibaba.druid.sql.ast.statement.SQLSelectItem;
@@ -41,6 +42,7 @@ import com.alibaba.druid.sql.ast.statement.SQLUnionQuery;
 import com.alibaba.druid.sql.dialect.db2.ast.stmt.DB2SelectQueryBlock;
 import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlSelectQueryBlock;
 import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlSelectQueryBlock.Limit;
+import com.alibaba.druid.sql.dialect.odps.ast.OdpsSelectQueryBlock;
 import com.alibaba.druid.sql.dialect.oracle.ast.stmt.OracleSelectQueryBlock;
 import com.alibaba.druid.sql.dialect.postgresql.ast.stmt.PGSelectQueryBlock;
 import com.alibaba.druid.sql.dialect.postgresql.ast.stmt.PGSelectQueryBlock.PGLimit;
@@ -447,4 +449,58 @@ public class PagerUtils {
             clearOrderBy(union.getRight());
         }
     }
+    
+    /**
+     * 
+     * @param sql
+     * @param dbType
+     * @return if not exists limit, return -1;
+     */
+    public static int getLimit(String sql, String dbType) {
+        List<SQLStatement> stmtList = SQLUtils.parseStatements(sql, dbType);
+
+        if (stmtList.size() != 1) {
+            return -1;
+        }
+
+        SQLStatement stmt = stmtList.get(0);
+
+        if (stmt instanceof SQLSelectStatement) {
+            SQLSelectStatement selectStmt = (SQLSelectStatement) stmt;
+            SQLSelectQuery query = selectStmt.getSelect().getQuery();
+            if (query instanceof SQLSelectQueryBlock) {
+                if (query instanceof MySqlSelectQueryBlock) {
+                    MySqlSelectQueryBlock.Limit limit = ((MySqlSelectQueryBlock) query).getLimit();
+
+                    if (limit == null) {
+                        return -1;
+                    }
+
+                    SQLExpr rowCountExpr = limit.getRowCount();
+
+                    if (rowCountExpr instanceof SQLNumericLiteralExpr) {
+                        int rowCount = ((SQLNumericLiteralExpr) rowCountExpr).getNumber().intValue();
+                        return rowCount;
+                    }
+
+                    return Integer.MAX_VALUE;
+                }
+
+                if (query instanceof OdpsSelectQueryBlock) {
+                    SQLExpr rowCountExpr = ((OdpsSelectQueryBlock) query).getLimit();
+
+                    if (rowCountExpr instanceof SQLNumericLiteralExpr) {
+                        int rowCount = ((SQLNumericLiteralExpr) rowCountExpr).getNumber().intValue();
+                        return rowCount;
+                    }
+
+                    return Integer.MAX_VALUE;
+                }
+
+                return -1;
+            }
+        }
+        
+        return -1;
+    }
 }

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

@@ -17,7 +17,6 @@ package com.alibaba.druid.sql.dialect.mysql.parser;
 
 import static com.alibaba.druid.sql.parser.CharTypes.isFirstIdentifierChar;
 import static com.alibaba.druid.sql.parser.LayoutCharacters.EOI;
-import static com.alibaba.druid.sql.parser.Token.LITERAL_CHARS;
 
 import java.util.HashMap;
 import java.util.Map;

src/main/java/com/alibaba/druid/sql/dialect/odps/parser/OdpsLexer.java

@@ -181,6 +181,34 @@ public class OdpsLexer extends Lexer {
 
     public void scanIdentifier() {
         final char first = ch;
+        
+        if (first == '`') {
+
+            mark = pos;
+            bufPos = 1;
+            char ch;
+            for (;;) {
+                ch = charAt(++pos);
+
+                if (ch == '`') {
+                    bufPos++;
+                    ch = charAt(++pos);
+                    break;
+                } else if (ch == EOI) {
+                    throw new ParserException("illegal identifier");
+                }
+
+                bufPos++;
+                continue;
+            }
+
+            this.ch = charAt(pos);
+
+            stringVal = subString(mark, bufPos);
+            token = Token.IDENTIFIER;
+            
+            return;
+        }
 
         final boolean firstFlag = isFirstIdentifierChar(first);
         if (!firstFlag) {