Main functions:
- Uppercase and lowercase conversion functions
- Get substring function (string intercept)
- Get string length function
- String Join function
- Remove substring function
- Character substitution functions
First, Case conversion
1, Upper: Turn capital
2. Lower: Turn lowercase
3. Initcap: Capitalize first letter
Second, get substring function (string intercept)
SUBSTR (Str,beginindex,endindex)
STR: string to be processed
Beginindex: start to intercept subscript position, >0 from the beginning of the head number subscript, <0 from the tail number subscript.
EndIndex: End subscript.
Third, get the length of the string
Length (str)
Four, string splicing
Concat (STR1,STR2): I think there's no ' | | ' Easy to use:
Five, remove the sub-characters
Trim (car from str): Remove all car from Str. Feel Chicken
LTrim (CAR,STR): Remove the first one from left
RTrim (CAR,STR): Remove the first one from right
Trim (str): Remove first space
Vi. replacement
Replace (STR1,STR2,STR3):
STR1: string to be processed
STR2: A string that needs to be replaced
STR3: Replace the string, the parameter can not write the same as the trim effect
Oracle built-in function (ii) Character functions