工作中有需要将线上数据导出到excel给客户分析/查看的情况，如下是方法介绍情况：
utl_file读写文件包 ，1分钟导出的数据量 大概是300万 适用于大量导出时
spool 循环打印 ，适用小型数据量时。    

1、创建用于导出数据的存储过程
利用utl_file导出.csv文件
首先在oracle数据库中建立sql_to_csv存储过程,代码如下:

CREATE OR REPLACE PROCEDURE SQL_TO_CSV
(
 P_QUERY IN VARCHAR2, -- PLSQL文
 P_DIR IN VARCHAR2, -- 导出的文件放置目录
 P_FILENAME IN VARCHAR2 -- CSV名
 )
 IS
  L_OUTPUT UTL_FILE.FILE_TYPE;
  L_THECURSOR INTEGER DEFAULT DBMS_SQL.OPEN_CURSOR;
  L_COLUMNVALUE VARCHAR2(4000);
  L_STATUS INTEGER;
  L_COLCNT NUMBER := 0;
  L_SEPARATOR VARCHAR2(1);
  L_DESCTBL DBMS_SQL.DESC_TAB;
  P_MAX_LINESIZE NUMBER := 32000;
BEGIN
  --OPEN FILE
  L_OUTPUT := UTL_FILE.FOPEN(P_DIR, P_FILENAME, 'W', P_MAX_LINESIZE);
  --DEFINE DATE FORMAT
  EXECUTE IMMEDIATE 'ALTER SESSION SET NLS_DATE_FORMAT=''YYYY-MM-DD HH24:MI:SS''';
  --OPEN CURSOR
  DBMS_SQL.PARSE(L_THECURSOR, P_QUERY, DBMS_SQL.NATIVE);
  DBMS_SQL.DESCRIBE_COLUMNS(L_THECURSOR, L_COLCNT, L_DESCTBL);
  --DUMP TABLE COLUMN NAME
  FOR I IN 1 .. L_COLCNT LOOP
    UTL_FILE.PUT(L_OUTPUT,L_SEPARATOR || '"' || L_DESCTBL(I).COL_NAME || '"'); --输出表字段
    DBMS_SQL.DEFINE_COLUMN(L_THECURSOR, I, L_COLUMNVALUE, 4000);
    L_SEPARATOR := ',';
  END LOOP;
  UTL_FILE.NEW_LINE(L_OUTPUT); --输出表字段
  --EXECUTE THE QUERY STATEMENT
  L_STATUS := DBMS_SQL.EXECUTE(L_THECURSOR);
 
  --DUMP TABLE COLUMN VALUE
  WHILE (DBMS_SQL.FETCH_ROWS(L_THECURSOR) > 0) LOOP
    L_SEPARATOR := '';
    FOR I IN 1 .. L_COLCNT LOOP
      DBMS_SQL.COLUMN_VALUE(L_THECURSOR, I, L_COLUMNVALUE);
      UTL_FILE.PUT(L_OUTPUT,
                  L_SEPARATOR || '"' ||
                  TRIM(BOTH ' ' FROM REPLACE(L_COLUMNVALUE, '"', '""')) || '"');
      L_SEPARATOR := ',';
    END LOOP;
    UTL_FILE.NEW_LINE(L_OUTPUT);
  END LOOP;
  --CLOSE CURSOR
  DBMS_SQL.CLOSE_CURSOR(L_THECURSOR);
  --CLOSE FILE
  UTL_FILE.FCLOSE(L_OUTPUT);
EXCEPTION
  WHEN OTHERS THEN
    RAISE;
END;
/

2、查询及创建 directory

set lines 200 pages 200
col owner for a30 
col directory_name for a30 
col directory_path for a85 
select * from dba_directories ;

OWNER                          DIRECTORY_NAME                 DIRECTORY_PATH
------------------------------ ------------------------------ -------------------------------------------------------------------------------------
SYS                            DATA                           /u01/app
SYS                            EXPDP_DIR                      /u01/app/expdp_bak
SYS                            XMLDIR                         /u01/app/oracle/product/11.2.0/dbhome_1/rdbms/xml
SYS                            ORACLE_OCM_CONFIG_DIR          /u01/app/oracle/product/11.2.0/dbhome_1/ccr/hosts/LG-MySQL-TestDB-92/state
SYS                            DATA_PUMP_DIR                  /u01/app/oracle/admin/lgdata/dpdump/
SYS                            ORACLE_OCM_CONFIG_DIR2         /u01/app/oracle/product/11.2.0/dbhome_1/ccr/state

或者创建directory

sql> create or replace directory OUT_PATH as '/u01/app/';

sql> grant read,write on directory OUT_PATH to public;

3、导出数据
3.1、数据库表导出语句

SQL> exec sql_to_csv('select * from LG_BANKNO_BNB_test','DATA','ehy.lg_bankno_bnb_test.csv');

PL/SQL procedure successfully completed.

3.2、带where 条件的sql

SQL> exec sql_to_csv('select * from LG_BANKNO_BNB_test where BANKCODE=402452106054','DATA','ehy.lg_bankno_bnb_test.csv');

PL/SQL procedure successfully completed.

3.3、带where 条件的sql 并且指定需要的列

SQL> exec sql_to_csv('select BANKCODE,BANKNAME from LG_BANKNO_BNB_test where BANKCODE=402452106054','DATA','ehy.lg_bankno_bnb_test.csv');

PL/SQL procedure successfully completed.

3.4、导出两表join的sql
具体SQL语句如下

select distinct b_BANKCODE,b_BANKNAME 
from (select a.BANKCODE as a_BANKCODE,a.BANKNAME as a_BANKNAME, 
             b.BANKCODE as b_BANKCODE,b.BANKNAME as b_BANKNAME 
        from LG_BANKNO_BNB a,LG_BANKNO_BNB_test b 
        where a.BANKCODE=b.BANKCODE) 
where a_BANKCODE is null ;

SQL> exec sql_to_csv('select distinct b_BANKCODE,b_BANKNAME from (select a.BANKCODE as a_BANKCODE,a.BANKNAME as a_BANKNAME, b.BANKCODE as b_BANKCODE, b.BANKNAME as b_BANKNAME from LG_BANKNO_BNB a,LG_BANKNO_BNB_test b where a.BANKCODE=b.BANKCODE) where a_BANKCODE is null','DATA','ehy.lg_bankno_bnb_test.csv');

PL/SQL procedure successfully completed.

说明：sql 必须一行书写，不能换行，否则会报错！！！
其实可以将上面的sql 先变成一个视图 view，然后再导出这个视图 view

3.5、导出视图的数据

create view sql_to_csv_view as
select distinct b_BANKCODE,b_BANKNAME 
from (select a.BANKCODE as a_BANKCODE,a.BANKNAME as a_BANKNAME, 
             b.BANKCODE as b_BANKCODE,b.BANKNAME as b_BANKNAME 
        from LG_BANKNO_BNB a,LG_BANKNO_BNB_test b 
        where a.BANKCODE =b.BANKCODE) 
where a_BANKCODE is not null ;

SQL> exec sql_to_csv('select * from sql_to_csv_view','DATA','ehy.lg_bankno_bnb_test.csv');

PL/SQL procedure successfully completed.

--删除视图
drop view sql_to_csv_view ;

3.6、生成批量导出数据

SELECT 'EXEC sql_to_csv(''select * from ' ||T.TABLE_NAME ||''',''DATA''' || ',''ODS_MDS.' || T.TABLE_NAME ||'.csv'');' FROM user_TABLES T where t.TABLE_NAME='表名' ;

# 生成的sql如下：
EXEC sql_to_csv('select * from LG_BANKNO_BNB_test','DATA','ehy.lg_bankno_bnb_test.csv');
EXEC sql_to_csv('select * from TD_DIS_BATCH_CHECK','DATA','ODS_MDS.TD_DIS_BATCH_CHECK.csv');
EXEC sql_to_csv('select * from TD_DIS_CONTROLL','DATA','ODS_MDS.TD_DIS_CONTROLL.csv');
EXEC sql_to_csv('select * from TD_DIS_TASK_DATASOURCE','DATA','ODS_MDS.TD_DIS_TASK_DATASOURCE.csv');
EXEC sql_to_csv('select * from TD_DIS_TASK_DEPENDENT','DATA','ODS_MDS.TD_DIS_TASK_DEPENDENT.csv');
EXEC sql_to_csv('select * from TD_DIS_TASK_GROUP','DATA','ODS_MDS.TD_DIS_TASK_GROUP.csv');