length usage in oracle
The LENGTH function returns the number of characters in a string. It accepts CHAR, VARCHAR2, NCHAR, and NVARCHAR2 data types as input, ignores whitespace, and returns an integer result.
Usage of LENGTH function in Oracle
LENGTH functionReturns the characters of string data number. It has the following format:
<code>LENGTH(string_expression)</code>
where:
- string_expression is the string expression whose length is to be found.
Syntax
The LENGTH function accepts the following data types as input:
- CHAR
- VARCHAR2
- NCHAR
- NVARCHAR2
Return value
LENGTH function returns an integer representing the number of characters in the string.
Example
The following example shows how to use the LENGTH function:
SELECT LENGTH('Hello World') FROM dual;
Output:
<code>10</code>
In the above example, LENGTH The function returns the number of characters in the string 'Hello World', which is 10.
Note
- LENGTH function does not consider spaces.
- The LENGTH function ignores trailing spaces.
- If string_expression is NULL, the LENGTH function returns NULL.
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