simplify a bit

Author: CommanderStorm

rust/mod.just

@@ -198,10 +198,7 @@ compress-db-statistics tile_dir db:
 
 # Diff two compressed sizes DBs (produced by `compress-db-statistics`).
 size-diff prev curr:
-    sqlite3 \
-      -cmd ".param set @prev '{{prev}}'" \
-      -cmd ".param set @curr '{{curr}}'" \
-      < scripts/diff.sql
+    sqlite3 {{curr}} ".attach '{{current_head}}' as current_head" < scripts/diff.sql
 
 # Download ~5k benchmark tiles (z0-z6) from Protomaps into outdir.
 # Skips if a previous complete download is detected (.complete sentinel).

rust/scripts/diff.sql

@@ -1,13 +1,10 @@
-ATTACH '{{prev}}' AS prev;
-ATTACH '{{curr}}' AS curr;
-
 CREATE TEMP VIEW changes AS
   SELECT z, x, y,
          p.size AS prev_size,
          c.size AS curr_size,
          c.size - p.size AS delta
-  FROM prev.sizes p
-  JOIN curr.sizes c USING (z, x, y);
+  FROM main.sizes p
+  JOIN current_head.sizes c USING (z, x, y);
 
 CREATE TEMP VIEW agg AS
   SELECT z,