VastbaseE100

操作符

• 求差集操作符：MINUS

  atlasdb=# select 1 minus select 1;
  

• 不等于操作符：^=

  atlasdb=# select 1^=1;
  -[ RECORD 1 ]
  ?column? | f
  

• 时间 + 整数操作符：date + int

  atlasdb=# select sysdate,sysdate+1;
  -[ RECORD 1 ]-----------------
  sysdate  | 2020-03-09 08:33:18
  ?column? | 2020-03-10 08:33:18
  

• 时间 - 整数操作符：date – int

  atlasdb=# 	-[ RECORD 1 ]-----------------
  sysdate  | 2020-03-09 08:33:46
  ?column? | 2020-02-27 08:33:46
  

• 时间 + 字符操作符：date + text

  atlasdb=# select sysdate,sysdate+11::text;
     sysdate       |      ?column?       
  ---------------------+---------------------
  2020-05-18 09:34:06 | 2020-05-29 09:34:06
  (1 row)
  

• 时间 - 字符操作符：date - text

  atlasdb=# select sysdate,sysdate-11::text;
     sysdate       |      ?column?       
  ---------------------+---------------------
  2020-05-18 09:33:54 | 2020-05-07 09:33:54
  (1 row)
  atlasdb=# select sysdate-'2020-05-18 09:52:00',sysdate;
  ?column? |       sysdate       
  ----------+---------------------
  0.001482 | 2020-05-18 09:54:08
  (1 row)
  

• 时间与字符的比较

  atlasdb=# select sysdate>'2020-05-17'::text,sysdate;
  ?column? |       sysdate       
  ----------+---------------------
  t        | 2020-05-18 09:36:28
  (1 row)
  
  atlasdb=# select sysdate>='2020-05-17'::text,sysdate;
  ?column? |       sysdate       
  ----------+---------------------
  t        | 2020-05-18 09:36:34
  (1 row)
  
  atlasdb=# select sysdate<'2020-05-17'::text,sysdate;
  ?column? |       sysdate       
  ----------+---------------------
  f        | 2020-05-18 09:36:37
  (1 row)
  
  atlasdb=# select sysdate<='2020-05-17'::text,sysdate;
  ?column? |       sysdate       
  ----------+---------------------
  f        | 2020-05-18 09:36:40
  (1 row)
  
  atlasdb=# select sysdate='2020-05-17'::text,sysdate;
  ?column? |       sysdate       
  ----------+---------------------
  f        | 2020-05-18 09:36:43
  (1 row)
  

• 时间 - 时间操作符：date – date

  atlasdb=# select sysdate-(sysdate-11);
  -[ RECORD 1 ]
  ?column? | 11
  

• 数值类型+/- 字符 操作符

  atlasdb=# select 1::bigint+'1'::text;
  ?column? 
  ----------
      2
  (1 row)
  
  atlasdb=# select 1::int+'1'::text;
  ?column? 
  ----------
      2
  (1 row)
  
  atlasdb=# select 1::smallint+'1'::text;
  ?column? 
  ----------
      2
  (1 row)
  atlasdb=#  select 1::bigint-'1'::text;
  ?column? 
  ----------
      0
  (1 row)
  
  atlasdb=#  select 1::int-'1'::text;
  ?column? 
  ----------
      0
  (1 row)
  
  atlasdb=#  select 1::smallint-'1'::text;
  ?column? 
  ----------
      0
  (1 row)
  atlasdb=# select 1.1::float+'1'::text;
  ?column? 
  ----------
    2.1
  (1 row)
  
  atlasdb=# select 1.1::double precision+'1'::text;
  ?column? 
  ----------
    2.1
  (1 row)
  atlasdb=# select 1.1::number+'1'::text;
  ?column? 
  ----------
    2.1
  (1 row)
  atlasdb=#  select 1.1::float-'1'::text;
  ?column? 
  ----------
    0.1
  (1 row)
  
  atlasdb=#  select 1.1::double precision-'1'::text;
  ?column? 
  ----------
    0.1
  (1 row)
  
  atlasdb=#  select 1.1::number-'1'::text;
  ?column? 
  ----------
    0.1
  (1 row)
  

• 数值类型 *、/ 字符 操作符

  atlasdb=#  select 3::smallint/'2'::text;
  ?column? 
  ----------
    1.5
  (1 row)
  
  atlasdb=# select 3::bigint/'2'::text;
    ?column?      
  --------------------
  1.5000000000000000
  (1 row)
  
  atlasdb=# select 3::int/'2'::text;
  ?column? 
  ----------
    1.5
  (1 row)
  
  atlasdb=# select 3::int*'2'::text;
  ?column? 
  ----------
      6
  (1 row)
  
  atlasdb=# select 3::bigint*'2'::text;
  ?column? 
  ----------
      6
  (1 row)
  
  atlasdb=# select 3::smallint*'2'::text;
  ?column? 
  ----------
      6
  (1 row)
  atlasdb=# select 3.8::float/'2'::text;
  ?column? 
  ----------
    1.9
  (1 row)
  atlasdb=# select 3.8::double precision /'2'::text;
  ?column? 
  ----------
    1.9
  (1 row)
  atlasdb=# select 3.8::number /'2'::text;
    ?column?      
  --------------------
  1.9000000000000000
  (1 row)
  

• 数值型与字符型的比较

  atlasdb=#  select 1='1'::text;
  ?column? 
  ----------
  t
  (1 row)
  
  atlasdb=# select 10='1'::text;
  ?column? 
  ----------
  f
  (1 row)
  
  atlasdb=# select 10>'1'::text;
  ?column? 
  ----------
  t
  (1 row)
  
  atlasdb=# select 10>='1'::text;
  ?column? 
  ----------
  t
  (1 row)
  
  atlasdb=# select 10<='1'::text;
  ?column? 
  ----------
  f
  (1 row)
  
  atlasdb=# select 10<'1'::text;
  ?column? 
  ----------
  f
  (1 row)
  
  atlasdb=# select 10<>'1'::text;
  ?column? 
  ----------
  t
  (1 row)
  atlasdb=# select 10::float <>'1'::text;
  ?column? 
  ----------
  t
  (1 row)
  
  atlasdb=# select 10::float >'1'::text;
  ?column? 
  ----------
  t
  (1 row)
  
  atlasdb=# select 10::float >='1'::text;
  ?column? 
  ----------
  t
  (1 row)
  
  atlasdb=# select 10::float <='1'::text;
  ?column? 
  ----------
  f
  (1 row)
  
  atlasdb=# select 10::float <'1'::text;
  ?column? 
  ----------
  f
  (1 row)
  

• 连接操作符||

  atlasdb=# select 'atlasdb'||2;
  ?column? 
  ----------
  atlasdb2
  (1 row)