生产中使用Oracle存储过程解决数据库查询缓慢问题

发布于2021-05-29 23:33 阅读(552) 评论(0) 点赞(19) 收藏(5)

生产上遇到了一个问题，有一段SQL语句需要查询信息，超级缓慢，语句如下：

SELECT extractvalue(d.document_data, '/root/deliveryNumber') AS deliveryNumber
FROM dat_document d
WHERE d.form_name     = 'SD04'
AND (document_status != 'deleted'
OR document_status   IS NULL )
AND extractvalue(d.document_data, '/root/deliveryNumber')    = '82844161';

由于Where后使用了oracle函数extractvalue破坏了索引查询，导致查询是全表扫描！，但是生产上dat_document 表数据量太大，而且给dat_document 增加extractvalue函数索引，风险性极高，特意采用了存储过程进行解决！通过定时或者手动执行存储过程，将从dat_document 查询替换成从中间表aac_sd04_tab 查询，查询效率提升飞速！

一、创建存储表和存储过程

表aac_sd04_tab

create table aac_sd04_tab (
    docid    varchar2(500),
    creator    varchar2(500),
    deliveryNumber varchar2(500),
    ordernum    varchar2(500)
  );
  --drop table aac_sd04_tab_son;
  --drop index aac_sd04tabindex;
     
  CREATE INDEX aac_sd04tabindex
  ON aac_sd04_tab (docid, deliverynumber);

存储过程savesd04，根据docid保存数据

PROCEDURE savesd04( docid IN VARCHAR2)
  AS
  BEGIN
  DELETE FROM aac_sd04_tab WHERE docid = docid;
  COMMIT;
  INSERT
  INTO aac_sd04_tab tab
    (
      tab.docid ,
      tab.creator ,
      tab.deliveryNumber,
      tab.ordernum 
    )
  SELECT 
    t.document_id,
    t.creator                                                              AS creator,
    extractvalue(t.document_data, '//root/deliveryNumber')                       AS deliveryNumber,   
    extractvalue(t.document_data, '//root/orderNum')                       AS ordernum                       
  FROM dat_document t
  WHERE t.document_id = docid
  AND t.form_name     = 'SD04' ;
  COMMIT;
EXCEPTION
WHEN OTHERS THEN
  dbms_output.put_line('saveSD04执行异常 docid=' || docid);
  ROLLBACK;
END;

存储过程savesd04all，保存所有数据

 procedure savesd04all as 
begin
  dbms_output.put_line('AAC_SD04_TAB  insert all');
  insert into aac_sd04_tab tab (
    tab.docid ,
      tab.creator ,
      tab.deliveryNumber,
      tab.ordernum 
  )
select 
    t.document_id,
    t.creator AS creator,
    extractvalue(t.document_data, '//root/deliveryNumber') AS deliveryNumber,   
    extractvalue(t.document_data, '//root/orderNum') AS ordernum                       
from
  dat_document t
where
  t.form_name = 'SD04';
commit;
EXCEPTION
        WHEN OTHERS THEN
            dbms_output.put_line('saveSD04执行异常');
            ROLLBACK;
end;

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二、创建存储过程

在这里插入图片描述
创建的存储过程名为PRC_SD04_ALL

create or replace PROCEDURE PRC_SD04_ALL
(
  docid IN VARCHAR2 
) AS 
BEGIN
 aac_document_pag.savesd04all;
END PRC_SD04_ALL;

savesd04all代表将所有数据批量写入到aac_sd04_tab中

三、执行存储过程

方式1：通过Oracle客户端执行存储过程
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方式2：通过Java后台代码执行

import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Types;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.gzsolartech.service.BaseDataService;
import org.hibernate.engine.spi.SessionFactoryImplementor;

@Service
public class CreateBusinessService extends BaseDataService{
//sproc存储过程名称
public boolean executePro(String sproc,String docId){
		Session session = null;
		Connection conn = null;
		boolean isSuccess = false;
		try {
			session = gdao.getSession();
			conn = ((SessionFactoryImplementor)session.getSessionFactory()).getConnectionProvider().getConnection();
			if(!StringUtils.isEmpty(sproc)){
				CallableStatement call = conn.prepareCall("{Call " + sproc + "(?)}");
				call.setString(1, docId);//设置输入参数
				isSuccess = call.execute();
			}
		} catch (Exception e) {
			
			LOG.error("------------------CreateBusinessService:"+e.getMessage());
		}finally{
			if(conn!=null){
				try {
					conn.close();
				} catch (SQLException e) {
					e.printStackTrace();
				}
			}
		}
		return isSuccess;
	}
}