| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you 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.cloud.upgrade.dao; |
| |
| import java.sql.Connection; |
| import java.sql.PreparedStatement; |
| import java.sql.SQLException; |
| |
| import org.apache.log4j.Logger; |
| |
| public class DatabaseAccessObject { |
| |
| private static Logger s_logger = Logger.getLogger(DatabaseAccessObject.class); |
| |
| public void dropKey(Connection conn, String tableName, String key, boolean isForeignKey) |
| { |
| String alter_sql_str; |
| if (isForeignKey) { |
| alter_sql_str = "ALTER TABLE " + tableName + " DROP FOREIGN KEY " + key; |
| } else { |
| alter_sql_str = "ALTER TABLE " + tableName + " DROP KEY " + key; |
| } |
| try(PreparedStatement pstmt = conn.prepareStatement(alter_sql_str);) |
| { |
| pstmt.executeUpdate(); |
| s_logger.debug("Key " + key + " is dropped successfully from the table " + tableName); |
| } catch (SQLException e) { |
| s_logger.debug("Ignored SQL Exception when trying to drop " + (isForeignKey ? "foreign " : "") + "key " + key + " on table " + tableName + " exception: " + e.getMessage()); |
| |
| } |
| } |
| |
| public void dropPrimaryKey(Connection conn, String tableName) { |
| try(PreparedStatement pstmt = conn.prepareStatement("ALTER TABLE " + tableName + " DROP PRIMARY KEY ");) { |
| pstmt.executeUpdate(); |
| s_logger.debug("Primary key is dropped successfully from the table " + tableName); |
| } catch (SQLException e) { |
| s_logger.debug("Ignored SQL Exception when trying to drop primary key on table " + tableName + " exception: " + e.getMessage()); |
| } |
| } |
| |
| public void dropColumn(Connection conn, String tableName, String columnName) { |
| try (PreparedStatement pstmt = conn.prepareStatement("ALTER TABLE " + tableName + " DROP COLUMN " + columnName);){ |
| pstmt.executeUpdate(); |
| s_logger.debug("Column " + columnName + " is dropped successfully from the table " + tableName); |
| } catch (SQLException e) { |
| s_logger.warn("Unable to drop column " + columnName + " due to exception", e); |
| } |
| } |
| |
| public boolean columnExists(Connection conn, String tableName, String columnName) { |
| boolean columnExists = false; |
| try (PreparedStatement pstmt = conn.prepareStatement("SELECT " + columnName + " FROM " + tableName);){ |
| pstmt.executeQuery(); |
| columnExists = true; |
| } catch (SQLException e) { |
| s_logger.debug("Field " + columnName + " doesn't exist in " + tableName + " ignoring exception: " + e.getMessage()); |
| } |
| return columnExists; |
| } |
| |
| protected static void closePreparedStatement(PreparedStatement pstmt, String errorMessage) { |
| try { |
| if (pstmt != null) { |
| pstmt.close(); |
| } |
| } catch (SQLException e) { |
| s_logger.warn(errorMessage, e); |
| } |
| } |
| |
| } |