To find the number of occurrences of a character in Oracle, perform the following steps: Get the total length of the string; Get the length of the substring where the character is located; Calculate the number of occurrences of a character: Subtract the substring from the total length length.
Find the number of times a character appears in Oracle
To find the number of times a character appears in Oracle, you can use LENGTH()
and SUBSTR()
functions. Here are the steps:
-
Use the
LENGTH()
function to get the total length of the string:SELECT LENGTH('your_string') FROM your_table;
-
Use the
SUBSTR()
function to get the length of the substring where the character is located:SELECT LENGTH(SUBSTR('your_string', start_position, end_position)) FROM your_table;
Among them:
-
start_position
is the starting position of the character to look for. -
end_position
is the end position of the character to look for.
-
-
Calculate the number of occurrences of a character:
Subtract the total length of the string obtained in step 1 from the total length obtained in step 2 Substring length.SELECT LENGTH('your_string') - LENGTH(SUBSTR('your_string', start_position, end_position)) FROM your_table;
Example:
Find the number of occurrences of the character "o" in the string "Hello World":
SELECT LENGTH('Hello World') - LENGTH(SUBSTR('Hello World', 2, 1)) FROM dual;
Result: 2
Notes:
- If the character is not in the string, the result will be 0.
- If you want to find multiple characters, you can use the
REPLACE()
function to replace all other characters first, then use the above steps.
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