What do you know about common DB2 functions? (1)

The following articles mainly introduce common DB2 functions. If you are interested in common DB2 functions, you can browse this article, the following is a detailed description of common DB2 functions. I hope you will understand this article after reading it.

1. type conversion functions:

 
 

  
  
decimal, double, Integer, smallint,real,Hex(arg),  
  
  
date, time,timestamp,char, varchar  
 
 

Common examples:

Convert to string type

 
 

  
  
Oracle: select to_char(15.5000) from dual;  
  
  
DB2: select char(15.5000) from sysibm.sysdummy1  
 
 

Converted to date and time

 
 

  
  
Oracle: select to_date('2008-01-01','yyyy-mm-dd') from dual;  
  
  
DB2: select date('2008-01-01') from sysibm.sysdummy1  
 
 

2. Date: year, quarter, month, week, day, hour, minute, second

Dayofyear (arg): returns the Daily Value of arg within the year.

Dayofweek (arg): returns the Daily Value of arg within a week.

Days (arg): returns the integer representation of the date, from-01-01.

Midnight_seconds (arg): the number of seconds between midnight and arg.

Monthname (arg): returns the month name of arg.

Dayname (arg): returns the week of arg.

Common examples:

Returns the current system time.

 
 

  
  
Oracle: select sysdate from dual;  
  
  
DB2: select current date from sysibm.sysdummy1  
 
 

Returns the next day of the current time)

 
 

  
  
Oracle: select sysdate,sysdate + interval '1' day from dual;  
  
  
DB2: select current date + 1 day from sysibm.sysdummy1  
 
 

3. String functions:

 
 

  
  
length,lcase, ucase, ltrim, rtrim 
 
 

Coalesce (arg1, arg2 ....) : The first non-null parameter in the returned parameter set.

Concat (arg1, arg2): connects two strings: arg1 and arg2.

Insert (arg1, pos, size, arg2): returns one. arg1 is deleted from the pos,

Insert arg2 to this location.

Left (arg, length): returns the leftmost length string of arg.

Locate (arg1, arg2, <pos>: Find the location where arg1 first appears in arg2, specify pos,

The first position of arg1 appears at the pos of arg2.

Posstr (arg1, arg2): returns the position where arg2 first appeared in arg1.

Repeat (arg1, num_times): returns the string that arg1 is repeated for num_times.

Replace (arg1, arg2, arg3): replace all arg2 in arg1 with arg3.

Right (arg, length): returns a string consisting of the Left length bytes of arg.

Space (arg): returns a string containing arg spaces.

Substr (arg1, pos, <length>: returns the length starting from the pos position in arg1. If the length is not specified, the remaining characters are returned.