How to Split String Words With Regexp_substr In Oracle Sql?

To split string words using the REGEXP_SUBSTR function in Oracle SQL, you can specify the regular expression pattern to match the words you want to extract from the string. The REGEXP_SUBSTR function returns the substring that matches the specified pattern.

For example, if you have a string 'Hello World' and you want to split it into individual words, you can use the following query:

SELECT REGEXP_SUBSTR('Hello World', '\w+', 1, LEVEL) AS word FROM dual CONNECT BY REGEXP_SUBSTR('Hello World', '\w+', 1, LEVEL) IS NOT NULL;

In this query, '\w+' is the regular expression pattern that matches one or more word characters. The LEVEL keyword is used to generate a row for each word in the string.

This query will return:

• Hello
• World

You can customize the regular expression pattern to match specific word patterns or delimiters in your string. By using the REGEXP_SUBSTR function in Oracle SQL, you can easily split string words based on a specified pattern.

How to split a string into sentences in Oracle SQL?

One way to split a string into sentences in Oracle SQL is to use a combination of the REGEXP_SUBSTR function and a regular expression pattern to identify sentence boundaries. Here's an example:

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WITH sample_data AS
(SELECT 'This is a sample sentence. And this is another one! Here is one more?' AS input_text FROM dual)

SELECT REGEXP_SUBSTR(input_text, '[^.!?]+', 1, LEVEL) as sentence
FROM sample_data
CONNECT BY REGEXP_SUBSTR(input_text, '[^.!?]+', 1, LEVEL) IS NOT NULL
AND PRIOR input_text = input_text
AND PRIOR SYS_GUID() IS NOT NULL;

In this example, the REGEXP_SUBSTR function is used to extract sequences of characters that do not contain periods, exclamation points, or question marks - which are common sentence terminators. The function is repeated for each occurrence of a sentence boundary using the CONNECT BY clause to generate output for each sentence.

How to split a string into lines in Oracle SQL?

To split a string into lines in Oracle SQL, you can use the REGEXP_SUBSTR function with the newline character as the delimiter. Here's an example:

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SELECT REGEXP_SUBSTR('Line 1\nLine 2\nLine 3', '[^' || CHR(10) || ']+', 1, LEVEL) AS line
FROM dual
CONNECT BY LEVEL <= REGEXP_COUNT('Line 1\nLine 2\nLine 3', '[^' || CHR(10) || ']+');

In this example, the REGEXP_SUBSTR function is used to extract each line from the input string based on the newline character (\n) as the delimiter. The CONNECT BY LEVEL construct is used to generate a series of numbers from 1 to the number of lines in the input string, and each iteration of the query extracts one line using the REGEXP_SUBSTR function. The result is a set of rows, each containing one line from the input string.

What is the difference between regexp_substr and substr in Oracle SQL?

The main difference between regexp_substr and substr in Oracle SQL is how they can be used to extract substrings from a string:

1. substr: The substr function in Oracle SQL is used to extract a specified substring from a string based on a given starting position and length. It takes in three parameters: the string to extract from, the starting position of the substring, and the length of the substring. For example, the following SQL query extracts a substring of length 3 starting at position 2 from the string 'Hello World':

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SELECT substr('Hello World', 2, 3) FROM dual;

This query would return 'ell'.

1. regexp_substr: The regexp_substr function in Oracle SQL is used to extract a substring from a string based on a regular expression pattern. It takes in three parameters: the string to extract from, the regular expression pattern to match, and the position to start searching from. For example, the following SQL query extracts the first word from the string 'Hello World':

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SELECT regexp_substr('Hello World', '\w+') FROM dual;

This query would return 'Hello'.

In summary, substr is used for simple substring extraction based on position and length, while regexp_substr is used for more complex substring extraction based on regular expression patterns.