sql 优化
有下面两个sql:
//查询出anz_client_account 表中cif_no, account_no重复的记录
select * from conv_data_ul_file_line fl
WHERE EXISTS (SELECT 1
FROM anz_client_account anz
WHERE EXISTS (SELECT 1
FROM anz_client_account aca
WHERE anz.cif_no = aca.cif_no
AND anz.account_no = aca.account_no
GROUP BY aca.cif_no, aca.account_no
HAVING COUNT(*) > 1)
AND fl.data_ul_file_line_oid = anz.data_ul_file_line_oid);
//查询出 anz_client_account表中cif_no从第五位到最后 不存在于client_info_ts表中cust_nbr字段
select * from conv_data_ul_file_line fl
WHERE EXISTS (SELECT 1
FROM anz_client_account anz
WHERE NOT EXISTS (SELECT 1 FROM client_info_ts ts WHERE ts.cust_nbr = substr(anz.cif_no, 5))
AND fl.data_ul_file_line_oid = anz.data_ul_file_line_oid);
这两个sql可进行优化?conv_data_ul_file_line,anz_client_account,client_info_ts中的数据非常多,以conv_data_ul_file_line中数据最多