Dynamic Management Views and Management Functions show what SQL Server is doing right now. The two scopes, the main categories and where to start.
SQL SERVER – UDF – Remove Duplicate Chars From String
A reader, Virendra Chauhan, shared a UDF that removes duplicate chars from one large string. Here is his REMOVE_DUPLICATE_INSTR function and how to call it.
ReorientObject: Swap a Geographic Ring’s Interior
ReorientObject swaps a geography polygon’s interior and exterior. Compare inside and outside witnesses, then reorient twice to restore membership.
OR in a JOIN: Preserve Matching Pairs When Rewriting
OR in a JOIN matches either key while returning each pair once. Compare NULL cases and pair counts before rewriting. Measure the actual plan only after proving the results.
STPointOnSurface: Choose a Point Inside a Polygon
STPointOnSurface returns an interior point. Check a polygon with a hole, a simple polygon and an empty geometry without assuming exact coordinates.
Finding the Right System View for the Question You Have
Choose SQL Server system views by the question they answer, distinguish catalog metadata from runtime counters, and understand reset boundaries.
AND and OR: Parentheses Make Predicate Precedence Clear
AND and OR predicates need explicit grouping. Use a complete small truth table to expose which alternatives share a common requirement.