What provides the means for matching and manipulating text strings in SQL?TF-IDFAssociation rulesRegular expressionsPACF

To address the provided question, we need to identify which of the given options is specifically designed for matching and manipulating text strings in SQL. Here are the details:

1. TF-IDF: This stands for Term Frequency-Inverse Document Frequency, a statistical measure used to evaluate the importance of a word in a document relative to a collection of documents (corpus). It is unrelated to direct string manipulation in SQL.

2. Association rules: These are used in data mining and machine learning for discovering interesting relations between variables in large databases. They are not focused on text string manipulation.

3. Regular expressions: These are sequences of characters that define a search pattern. This is specifically designed for the purpose of matching strings, making it the most relevant for searching and manipulating text within SQL queries.

4. PACF (Partial Autocorrelation Function): This is a statistical function used in time series analysis, not for matching text strings in SQL.

Final Answer

The correct option is Regular expressions, as they provide the means for matching and manipulating text strings in SQL.