chore: import upstream snapshot with attribution

examples/SQLPage developer user interface/sqlpage/migrations/00001_table_contents.sql

@@ -0,0 +1,10 @@
+-- Given a table name as text, return the contents of the table as a set of json objects
+-- Safely escapes the table name to prevent SQL injection.
+-- Accepts only normal tables, not postgres system tables.
+CREATE OR REPLACE FUNCTION table_contents (table_name text)
+RETURNS SETOF json AS $$
+BEGIN
+  RETURN QUERY EXECUTE
+    format('SELECT row_to_json(%I) FROM %I', table_name, table_name);
+END;
+$$ LANGUAGE plpgsql;

examples/SQLPage developer user interface/sqlpage/migrations/0000_create_sqlpage_files_table.sql

@@ -0,0 +1,20 @@
+CREATE TABLE
+  sqlpage_files (
+    path VARCHAR(255) NOT NULL PRIMARY KEY,
+    contents BYTEA NOT NULL,
+    last_modified TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
+  );
+
+-- automatically update last_modified timestamp
+
+CREATE OR REPLACE FUNCTION update_last_modified_sqlpage_files()
+RETURNS TRIGGER AS $$
+BEGIN
+  NEW.last_modified = CURRENT_TIMESTAMP;
+  RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE TRIGGER update_last_modified BEFORE
+UPDATE ON sqlpage_files FOR EACH ROW
+EXECUTE PROCEDURE update_last_modified_sqlpage_files();