Oracle string manipulation: stitching, replacing, intercepting, finding

First, stitching strings

1. Use "| |" To stitch Strings:

Select ' Stitching ' || ' string '  as Str  from student;

2, using the concat (PARAM1,PARAM2) function to achieve:

Select concat (' concatenation ',' string 'asStr  from student;

Note: Oracle's Concat () method supports only two parameters, and if you stitch multiple parameters, you can nest concat ():

Select concat (concat (' concatenation ',' string '),'  AB'asStr from student;

Ii. Interception of strings

SUBSTR (String,start_position,[length]), get substring

String: Source string

Start_position: Start position

Length: string lengths [optional]

1substr ("ABCDEFG",0);//return: ABCDEFG, intercept all characters2substr ("ABCDEFG",2);//return: CDEFG, intercept all characters after starting with C3substr ("ABCDEFG",0,3);//return: ABC, intercept starting from a 3 characters4substr ("ABCDEFG",0, -);//return: abcdefg,100 The maximum number of preprocessed strings is returned, although it exceeds the length of the preprocessed string, but does not affect the return result. 5substr ("ABCDEFG",-3);//Back to: EFG, note parameters-3, a negative value indicates that the string is positioned unchanged from the beginning of the tail.

Third, find the string

INSTR (string,substring,position,ocurrence) Find string position

String: Source string
SubString: substring to find
Position: Where to find start
Ocurrence: A substring of the first occurrence of a source string

Select INSTR ('CORPORATEfloor','OR'32as   from

Iv. replacing strings

Replace (strsource, STR1, STR2) replaces str1 in strsource with str2

Strsource: Source string

STR1: the string to replace

STR2: Replaced string

Select ' Replace string '  as Replace (' replace string ' ' replace  ' ' modify  '  as  from dual

Note: This article refers to the original: https://www.cnblogs.com/smallrock/p/3507022.html

Oracle string manipulation: stitching, replacing, intercepting, finding