package eb.controller.core;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import javax.servlet.UnavailableException;
import com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException;
/**
-
@author Bicashy,fencer911(for Mysql Version)
*/
public class TableOperate {
static Statement stmt = null;
static Connection conn = null;
static Map map = new HashMap(); //用来保存已经删除了的表的集合
static Map filterMap = new HashMap(); //用来保存需要过滤的表的集合static String schema ;
/**- 获得数据库链接
- @return / private static Connection getConnection(){ try { Class.forName( "com.mysql.jdbc.Driver").newInstance(); //String url= "jdbc:oracle:thin:@10.45.10.177:1521:highway"; String url= "jdbc:mysql://localhost:3306/eb?useUnicode=true&characterEncoding=utf-8"; String user= "root"; String password= "eryue1818*"; schema = user; conn = DriverManager.getConnection(url,user,password); return conn; } catch (InstantiationException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IllegalAccessException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; }
/**
- 获得该用户的所有表,并删除表（除了要过滤的表） */ private static void findDeleteTableSQL(){ if(conn!=null){ try { stmt=conn.createStatement(); String sql = "show TABLES"; //找到该链接用户的所有表 ResultSet rs=stmt.executeQuery(sql); while(rs.next()){ String tabName = rs.getString(1); //getString("table_name"); //如果map中包含了表名,说明已经删除过了 //如果filterMap中包含了表名,则不删除 if(!map.containsKey(tabName)&&!filterMap.containsKey(tabName)){ printDeleteTableSQL(tabName); } } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }
/**
- 删除表，并将删除表的语句输出到控制台(记录后方便在数据库客户端执行)
- @param l
- @param tableName
-
@return
*/
private static void printDeleteTableSQL(String tableName){
String sql = "DELETE FROM "+tableName.toUpperCase();
try {
stmt=conn.createStatement();
System.out.println(sql+";");
stmt.execute(sql);
stmt.close();
//将删除语句输出到控制台
map.put(tableName,null);
} catch (MySQLIntegrityConstraintViolationException e) {
// TODO Auto-generated catch block
String error = e.toString();
System.out.println(error);int p1=error.indexOf("("); int p2=error.indexOf("FOREIGN KEY"); error=error.substring(p1, p2); int p3=error.indexOf("CONSTRAINT"); error=error.substring(p3); error=error.replaceAll("CONSTRAINT", "").replaceAll(" ", "").replaceAll("`", ""); //截取错误信息得到外键约束名称 String fk_constraints =error; System.out.println("fk_constraints"+fk_constraints); deleteTableNameFromFK(fk_constraints); //删除外键约束表后,就可以将本表删掉 printDeleteTableSQL(tableName);}catch (Exception e) {
System.out.println(e.toString());
}
}
/**
- 删除通过外键约束找到的有子记录的表
- @param fk_constraints */ private static void deleteTableNameFromFK(String fk_constraints){ String sql = "select table_name from information_schema.REFERENTIAL_CONSTRAINTS where constraint_schema='laidong8v5' and constraint_name='"+fk_constraints+"'"; try { ResultSet rs=stmt.executeQuery(sql); while(rs.next()){ String tabN = rs.getString("table_name"); printDeleteTableSQL(tabN);//递归 } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } }
/**
- 初始化需要过滤表的集合(该表如果是别的表的外键关联表也有可能被删除) */ private static void initFilterMap(){ String[] tables = {"ETC_USER","etc_dic_data","MENU","admin"}; for (int j = 0; j < tables.length; j++) { filterMap.put(tables[j].toUpperCase(),null); } }
public static void main(String[] args) {
getConnection();
//initFilterMap();//初始化不需要删除的表//删除该用户下所有表（除了需要过滤的）,并获得删除语句 findDeleteTableSQL(); //删除某一个表（有外键约束的表将先删除）,并获得删除语句 //printDeleteTableSQL("obu_mast");}
}
在外面看到，试了之后发现它把所有的表全都删除了，现在不知道怎么添加过滤的表，该怎么写。
