String Pattern Matching with Wildcards constitutes a formal mechanism for defining subsets within linear character sequences using symbolic placeholders to represent unknown or variable-length substrings. This domain belongs to the intersection of theoretical computer science and relational database theory, specifically functioning as a specialized subset of regular expression logic adapted for standard SQL query structures. The core principle relies on the substitution model where predefined wildcard characters abstract specific byte values, enabling efficient index-based pruning during set retrieval operations without traversing every potential character combination in a candidate dataset.
Pattern matching in SQL lets a query filter rows on the *shape* of text rather than an exact value, using the `LIKE` operator together with wildcard characters inside a quoted pattern. The two standa…