Question

我正在尝试从ORACLE表中检索具有昨天日期的记录。我每天都有一份工作，只检索昨天的记录。

注意**列insert_date的类型为date

这是我到目前为止的两个SQL语句：

SELECT distinct column1
  FROM table1
 WHERE flag = 'N'  
   AND insert_date BETWEEN TRUNC(CURRENT_DATE-1) AND TRUNC(CURRENT_DATE) 
   AND ipaddress IS NOT NULL
   AND ipaddress <> '0.0.0.0';

和

SELECT distinct column1 
  FROM table1
 WHERE flag = 'N'  
   AND insert_date 
       BETWEEN To_Timestamp(CONCAT (to_char(CURRENT_DATE-1),' 12:00:00 AM')) 
           AND To_Timestamp(Concat (to_char(CURRENT_DATE-1),' 11:59:59 PM')) 
   AND ipaddress IS NOT NULL 
   AND ipaddress <> '0.0.0.0';

似乎这两个SQL语句产生相同的输出。但是，我不是ORACLE的专家，所以我想询问社区是否有任何我不知道的“陷阱”。

Answer 1

试试这个：

SELECT distinct column1
 FROM table1
 WHERE flag = 'N'  AND
  insert_date = trunc(sysdate-1,'DD')
   and ipaddress is not null and ipaddress<>'0.0.0.0';

您的第一个查询工作正常，但如果您想要过滤一天的数据，则可能不需要使用between。

Answer 2

使用中间值但从结束日期减去秒。

insert_date between trunc(CURRENT_DATE-1) and trunc(CURRENT_DATE) - 1/86400

Answer 3

to_Timestamp(Concat (to_char(CURRENT_DATE-1),' 12:00:00 AM'))

是非常多余的，我认为这是另一种方法的原因（trunc(current_date-1)）

只有“陷阱”我才能看到日期完全 12:00:00 am的记录将包含在第二个查询中但不包含在第一个查询中。

有一种非常简单的方法可以检查这类问题：

SELECT distinct column1
FROM table1
WHERE flag = 'N'  AND insert_date between trunc(CURRENT_DATE-1)
    and trunc(CURRENT_DATE) and ipaddress is not null and ipaddress<>'0.0.0.0';
MINUS
SELECT distinct column1 
FROM table1
WHERE flag = 'N'  
      AND insert_date between To_Timestamp(Concat (to_char(CURRENT_DATE-1),' 12:00:00 AM'))                         and To_Timestamp(Concat (to_char(CURRENT_DATE-1),' 11:59:59 PM')) 
      and ipaddress is not null and ipaddress<>'0.0.0.0';

和

SELECT distinct column1 
FROM table1
WHERE flag = 'N'  
      AND insert_date between To_Timestamp(Concat (to_char(CURRENT_DATE-1),' 12:00:00 AM'))                         and To_Timestamp(Concat (to_char(CURRENT_DATE-1),' 11:59:59 PM')) 
      and ipaddress is not null and ipaddress<>'0.0.0.0';
MINUS
SELECT distinct column1
FROM table1
WHERE flag = 'N'  AND insert_date between trunc(CURRENT_DATE-1)
    and trunc(CURRENT_DATE) and ipaddress is not null and ipaddress<>'0.0.0.0';

如果从这些查询中获得结果，那么这意味着两种方法并不完全相同。

搜索前一天的记录

3 个答案: