JDBC模糊查询的4种方式

1：%放在占位符中
              parameters.add("%"+familyMemberQueryBean.getFullName()+"%");
              sql+=" and t.full_name like ?";

2：使用concat函数
                parameters.add(familyMemberQueryBean.getFullName());
                sql+=" and t.full_name like concat('%',?,'%')";

3：使用转义字符\，百分号直接写在sql语句中
                parameters.add(familyMemberQueryBean.getFullName());
                sql+=" and t.full_name like \"%\"?\"%\"";

直接查询的SQL语句如下：SELECT id,full_name,email,phone,remark FROM family_member t WHERE 1 = 1
                                                AND t.full_name LIKE "%"'李'"%" AND t.email LIKE "%"'qq'"%"

4：直接拼接SQL
                sql+=" and t.full_name like '%"+familyMemberQueryBean.getFullName()+"%'";

例如：

 package org.pine.dao.impl;
 
 import org.pine.dao.FamilyMemberDao;
 import org.pine.dto.FamilyMember;
 import org.pine.util.DbcpUtils;
 import org.pine.vo.FamilyMemberQueryBean;
 import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.util.ArrayList;
 import java.util.List;
 
 /**
  * FamilyMemberDao实现类
  *
  * @Auther: zts
  * @Date: 2019/5/28 下午 03:21
  * @version: 1.0
  */
 public class FamilyMemberDaoImpl implements FamilyMemberDao {
     /*
     public List<FamilyMember> queryFamilyMembers(FamilyMemberQueryBean familyMemberQueryBean) {
         Connection connection =null;
         PreparedStatement preparedStatement=null;
         ResultSet resultSet=null;
         try {
             connection = DbcpUtils.getConnection();
             String sql ="SELECT id,full_name,email,phone,remark FROM family_member t WHERE 1 = 1 ";
             //拼接SQL
             List<Object> parameters = new ArrayList<Object>();
             if(familyMemberQueryBean.getFullName()!=null&&familyMemberQueryBean.getFullName().length()>0){
               parameters.add("%"+familyMemberQueryBean.getFullName()+"%");
               sql+=" and t.full_name like ?";
             }
             if(familyMemberQueryBean.getEmail()!=null&&familyMemberQueryBean.getEmail().length()>0){
               parameters.add("%"+familyMemberQueryBean.getEmail()+"%");
               sql+=" and t.email like ?";
             }
             if(familyMemberQueryBean.getPhone()!=null&&familyMemberQueryBean.getPhone().length()>0){
               parameters.add("%"+familyMemberQueryBean.getPhone()+"%");
               sql+=" and t.phone like ?";
             }
             if(familyMemberQueryBean.getRemark()!=null&&familyMemberQueryBean.getRemark().length()>0){
               parameters.add("%"+familyMemberQueryBean.getRemark()+"%");
               sql+=" and t.remark like ?";
             }
             sql+="limit ?,?";
             parameters.add(familyMemberQueryBean.getStart());
             parameters.add(familyMemberQueryBean.getLimit());
             DbcpUtils.printlnSQL(sql);
             DbcpUtils.printlnParameters(parameters);
             preparedStatement = connection.prepareStatement(sql);
             //设置参数
             for(int i=0;i<parameters.size();i++){
                 preparedStatement.setObject(i+1,parameters.get(i));
             }
             resultSet = preparedStatement.executeQuery();
             List<FamilyMember> familyMembers = new ArrayList<FamilyMember>();
             while (resultSet.next()){
                 FamilyMember familyMember = new FamilyMember();
                 int id = resultSet.getInt("id");
                 String fullName = resultSet.getString("full_name");
                 String email = resultSet.getString("email");
                 String phone = resultSet.getString("phone");
                 String remark = resultSet.getString("remark");
                 familyMember.setId(id);
                 familyMember.setFullName(fullName);
                 familyMember.setEmail(email);
                 familyMember.setPhone(phone);
                 familyMember.setRemark(remark);
                 familyMembers.add(familyMember);
             }
             return familyMembers;
         }catch (Exception e){
             throw  new RuntimeException(e);
         }finally {
             DbcpUtils.closeConnection(connection,preparedStatement,resultSet);
         }
     }*/
 
     /*
     @Override
     public int queryFamilyMemberCount(FamilyMemberQueryBean familyMemberQueryBean) {
         Connection connection =null;
         PreparedStatement preparedStatement=null;
         ResultSet resultSet=null;
         try {
             connection = DbcpUtils.getConnection();
             String sql ="SELECT count(*) FROM family_member t WHERE 1 = 1 ";
             //拼接SQL
             List<String> parameters = new ArrayList<String>();
             if(familyMemberQueryBean.getFullName()!=null&&familyMemberQueryBean.getFullName().length()>0){
                 parameters.add(familyMemberQueryBean.getFullName());
                 sql+=" and t.full_name like concat('%',?,'%')";
             }
             if(familyMemberQueryBean.getEmail()!=null&&familyMemberQueryBean.getEmail().length()>0){
                 parameters.add(familyMemberQueryBean.getEmail());
                 sql+=" and t.email like concat('%',?,'%')";
             }
             if(familyMemberQueryBean.getPhone()!=null&&familyMemberQueryBean.getPhone().length()>0){
                 parameters.add(familyMemberQueryBean.getPhone());
                 sql+=" and t.phone like concat('%',?,'%')";
             }
             if(familyMemberQueryBean.getRemark()!=null&&familyMemberQueryBean.getRemark().length()>0){
                 parameters.add(familyMemberQueryBean.getRemark());
                 sql+=" and t.remark like concat('%',?,'%')";
             }
             DbcpUtils.printlnSQL(sql);
             DbcpUtils.printlnParameters(parameters);
             preparedStatement = connection.prepareStatement(sql);
             //设置参数
             for(int i=0;i<parameters.size();i++){
                 preparedStatement.setString(i+1,parameters.get(i));
             }
             resultSet = preparedStatement.executeQuery();
             resultSet.next();
             int count = resultSet.getInt(1);
             return count;
         }catch (Exception e){
             throw  new RuntimeException(e);
         }finally {
             DbcpUtils.closeConnection(connection,preparedStatement,resultSet);
         }
     }*/
 
     public List<FamilyMember> queryFamilyMembers(FamilyMemberQueryBean familyMemberQueryBean) {
         Connection connection =null;
         PreparedStatement preparedStatement=null;
         ResultSet resultSet=null;
         try {
             connection = DbcpUtils.getConnection();
             String sql ="SELECT id,full_name,email,phone,remark FROM family_member t WHERE 1 = 1 ";
             //拼接SQL
             List<Object> parameters = new ArrayList<Object>();
             if(familyMemberQueryBean.getFullName()!=null&&familyMemberQueryBean.getFullName().length()>0){
                 parameters.add(familyMemberQueryBean.getFullName());
                 sql+=" and t.full_name like \"%\"?\"%\"";
             }
             if(familyMemberQueryBean.getEmail()!=null&&familyMemberQueryBean.getEmail().length()>0){
                 parameters.add(familyMemberQueryBean.getEmail());
                 sql+=" and t.email like \"%\"?\"%\"";
             }
             if(familyMemberQueryBean.getPhone()!=null&&familyMemberQueryBean.getPhone().length()>0){
                 parameters.add(familyMemberQueryBean.getPhone());
                 sql+=" and t.phone like \"%\"?\"%\"";
             }
             if(familyMemberQueryBean.getRemark()!=null&&familyMemberQueryBean.getRemark().length()>0){
                 parameters.add(familyMemberQueryBean.getRemark());
                 sql+=" and t.remark like \"%\"?\"%\"";
             }
             sql+=" limit ?,?";
             parameters.add(familyMemberQueryBean.getStart());
             parameters.add(familyMemberQueryBean.getLimit());
             DbcpUtils.printlnSQL(sql);
             DbcpUtils.printlnParameters(parameters);
             preparedStatement = connection.prepareStatement(sql);
             //设置参数
             for(int i=0;i<parameters.size();i++){
                 preparedStatement.setObject(i+1,parameters.get(i));
             }
             resultSet = preparedStatement.executeQuery();
             List<FamilyMember> familyMembers = new ArrayList<FamilyMember>();
             while (resultSet.next()){
                 FamilyMember familyMember = new FamilyMember();
                 int id = resultSet.getInt("id");
                 String fullName = resultSet.getString("full_name");
                 String email = resultSet.getString("email");
                 String phone = resultSet.getString("phone");
                 String remark = resultSet.getString("remark");
                 familyMember.setId(id);
                 familyMember.setFullName(fullName);
                 familyMember.setEmail(email);
                 familyMember.setPhone(phone);
                 familyMember.setRemark(remark);
                 familyMembers.add(familyMember);
             }
             return familyMembers;
         }catch (Exception e){
             throw  new RuntimeException(e);
         }finally {
             DbcpUtils.closeConnection(connection,preparedStatement,resultSet);
         }
     }
 
     @Override
     public int queryFamilyMemberCount(FamilyMemberQueryBean familyMemberQueryBean) {
         Connection connection =null;
         PreparedStatement preparedStatement=null;
         ResultSet resultSet=null;
         try {
             connection = DbcpUtils.getConnection();
             String sql ="SELECT count(*) FROM family_member t WHERE 1 = 1 ";
             //拼接SQL
             List<String> parameters = new ArrayList<String>();
             if(familyMemberQueryBean.getFullName()!=null&&familyMemberQueryBean.getFullName().length()>0){
                 sql+=" and t.full_name like '%"+familyMemberQueryBean.getFullName()+"%'";
             }
             if(familyMemberQueryBean.getEmail()!=null&&familyMemberQueryBean.getEmail().length()>0){
                 sql+=" and t.email like '%"+familyMemberQueryBean.getEmail()+"%'";
             }
             if(familyMemberQueryBean.getPhone()!=null&&familyMemberQueryBean.getPhone().length()>0){
                 sql+=" and t.phone like '%"+familyMemberQueryBean.getPhone()+"%'";
             }
             if(familyMemberQueryBean.getRemark()!=null&&familyMemberQueryBean.getRemark().length()>0){
                 sql+=" and t.remark like '"+familyMemberQueryBean.getRemark()+"'";
             }
             DbcpUtils.printlnSQL(sql);
             DbcpUtils.printlnParameters(parameters);
             preparedStatement = connection.prepareStatement(sql);
             //设置参数
             for(int i=0;i<parameters.size();i++){
                 preparedStatement.setString(i+1,parameters.get(i));
             }
             resultSet = preparedStatement.executeQuery();
             resultSet.next();
             int count = resultSet.getInt(1);
             return count;
         }catch (Exception e){
             throw  new RuntimeException(e);
         }finally {
             DbcpUtils.closeConnection(connection,preparedStatement,resultSet);
         }
     }
 }