Data update

Task/String-matching/DuckDB/string-matching.duckdb

@@ -0,0 +1,17 @@
+# Return a list of the indices of all occurrences (including overlapping occurrences)
+create or replace function string_positions(haystack, needle) as (
+  WITH RECURSIVE etc AS (
+    SELECT
+      position(needle IN haystack) AS start_pos,
+      0 as s
+    UNION ALL
+    SELECT
+      position(needle IN substr(haystack, start_pos + 1)) + start_pos AS start_pos,
+      start_pos as s
+    FROM etc
+    WHERE start_pos != s
+  )
+  SELECT coalesce(array_agg(start_pos order by start_pos),[]::BIGINT[])
+  FROM etc
+  WHERE start_pos > 0 and s != start_pos
+);