Escape the LIKE pattern special chars, using as the escape character. The LIKE patterns produced by #visitStartsWith, #visitEndsWith and #visitContains declare ESCAPE '', so the wildcards _ and % and the escape character itself must each be prefixed with to be matched literally.

Note: This method adopts the escape representation within Spark and is not bound to any JDBC dialect. A JDBC dialect should overwrite this API if the underlying database has more LIKE special chars than _, % and . Escaping that is instead needed because the database treats a character specially inside a SQL string literal belongs in #escapeStringLiteralForLikePattern.

Escape the characters that the target database treats specially inside a SQL string literal, applied to a LIKE pattern (and its ESCAPE character) when embedding it into a '...' literal for predicate pushdown.

The default returns the input unchanged: a standard SQL string literal is taken verbatim (the single-quote doubling is already applied when the literal is rendered), so the that #escapeSpecialCharsForLikePattern uses as the LIKE escape character reaches the LIKE engine intact. A dialect whose string-literal syntax gives a special meaning (e.g. MySQL, which treats as an escape character inside string literals) must override this to double the backslash, so the LIKE pattern survives string-literal parsing unchanged.

Builds SQL for an aggregate function.

In V2ExpressionSQLBuilder, always use this override (with Expression[]) instead of the String[] version, as the String[] version does not validate whether the function is supported in JDBC dialects.