我在创建小表上测试了这个编码SQL,它有4行数据,我得到快速查询但是当我更改为真表深度时并且不给我任何结果时,这个真值表它有超过100万条记录
SELECT DISTINCT /*+ richs_secret_hint */
em_code, (to_date(end_date,'DD-MM-YYYY') - level + 1) AS days
FROM
islaam_vca where em_code = '2222'
CONNECT BY level <= (to_date(end_date,'DD-MM-YYYY') - to_date(start_date,'DD-MM-YYYY') + 1)
order by days ASC
;
给我快速的结果
任何人都帮助我如何从真值表中获得快速结果
CREATE UNIQUE INDEX islaam_vca_uk1 ON islaam_vca(em_code, start_date)
SELECT /*+ALL_ROWS*/ distinct em_code --sorry about my interpretation of secret your hint
, start_date
, NVL(end_date, SYSDATE) end_date --don't know if end date is nullable or now
, TRUNC(start_date) + level - 1 specific_date
FROM (SELECT em_code
, start_date
, end_date
FROM islaam_vca
WHERE em_code = '2222')
CONNECT BY level <= TRUNC(NVL(end_date, SYSDATE)) - TRUNC(start_date) + 1
order by specific_date;