diff --git a/Cargo.lock b/Cargo.lock
index fbdfe457a..097c9d88e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2978,9 +2978,9 @@ dependencies = [
 
 [[package]]
 name = "sqlite-hashes"
-version = "0.3.2"
+version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f756a7c1f66e2d70c9acb5881776ba0ae25ba2aaf68e2f69ed32d96c42313fab"
+checksum = "fd203121770e67b5f689ebf9592c88d3529193743f35630413f419be8ef1e835"
 dependencies = [
  "digest",
  "md-5",
diff --git a/docs/src/tools.md b/docs/src/tools.md
index d59d8e6cb..a2e35b5e0 100644
--- a/docs/src/tools.md
+++ b/docs/src/tools.md
@@ -74,7 +74,7 @@ The original [MBTiles specification](https://github.com/mapbox/mbtiles-spec#read
 
 A typical Normalized schema generated by tools like [tilelive-copy](https://github.com/mapbox/TileLive#bintilelive-copy) use MD5 hash in the `tile_id` column. The Martin's `mbtiles` tool can use this hash to verify the content of each tile. We also define a new `flat-with-hash` schema that stores the hash and tile data in the same table. This schema is more efficient than the `normalized` schema when data has no duplicate tiles (see below). Per tile validation is not available for `flat` schema.
 
-Per-tile validation will catch individual invalid tiles, but it will not detect overall datastore corruption (e.g. missing tiles or tiles that shouldn't exist, or tiles with incorrect z/x/y values).  For that, Martin `mbtiles` tool defines a new metadata value called `agg_tiles_hash`. The value is computed by hashing  `cast(zoom_level AS text), cast(tile_column AS text), cast(tile_row AS text), tile_data` combined for all rows in the `tiles` table/view, ordered by z,x,y. In case there are no rows or all are NULL, the hash value of an empty string is used.
+Per-tile validation will catch individual invalid tiles, but it will not detect overall datastore corruption (e.g. missing tiles or tiles that shouldn't exist, or tiles with incorrect z/x/y values).  For that, Martin `mbtiles` tool defines a new metadata value called `agg_tiles_hash`. The value is computed by hashing  `cast(zoom_level AS text), cast(tile_column AS text), cast(tile_row AS text), cast(tile_data as blob)` combined for all rows in the `tiles` table/view, ordered by z,x,y. In case there are no rows or all are NULL, the hash value of an empty string is used.
 
 The `mbtiles` tool will compute `agg_tiles_hash` value when copying or validating mbtiles files.
 
diff --git a/martin-mbtiles/src/mbtiles.rs b/martin-mbtiles/src/mbtiles.rs
index ce4bb93eb..b37cbd8df 100644
--- a/martin-mbtiles/src/mbtiles.rs
+++ b/martin-mbtiles/src/mbtiles.rs
@@ -564,20 +564,21 @@ where
     let query = query(
         // The md5_concat func will return NULL if there are no rows in the tiles table.
         // For our use case, we will treat it as an empty string, and hash that.
+        // Note that in some weird rare cases, a column with blob type may be stored as an integer value
         "SELECT
-             hex(
-               coalesce(
-                 md5_concat(
-                   cast(zoom_level AS text),
-                   cast(tile_column AS text),
-                   cast(tile_row AS text),
-                   tile_data
-                 ),
-                 md5('')
-               )
-             )
-             FROM tiles
-             ORDER BY zoom_level, tile_column, tile_row;",
+         hex(
+           coalesce(
+             md5_concat(
+               cast(zoom_level AS text),
+               cast(tile_column AS text),
+               cast(tile_row AS text),
+               cast(tile_data as blob)
+             ),
+             md5('')
+           )
+         )
+         FROM tiles
+         ORDER BY zoom_level, tile_column, tile_row;",
     );
     Ok(query.fetch_one(conn).await?.get::<String, _>(0))
 }