diff --git a/catalogue/CMakeLists.txt b/catalogue/CMakeLists.txt
index abcf276ca51fe4551553e254b3065acf45e78641..5f1bc9aefebfd22f95b4b387aeff9162f1b9099f 100644
--- a/catalogue/CMakeLists.txt
+++ b/catalogue/CMakeLists.txt
@@ -101,7 +101,7 @@ add_custom_command (OUTPUT sqlite_catalogue_schema.sql mysql_catalogue_schema.sq
     ${CMAKE_CURRENT_SOURCE_DIR}/mysql_catalogue_schema_header.sql 
     ${CMAKE_CURRENT_SOURCE_DIR}/common_catalogue_schema.sql 
     ${CMAKE_CURRENT_SOURCE_DIR}/mysql_catalogue_schema_trailer.sql
-    | sed 's/NUMERIC\([^\)]*\)/BIGINT/g'
+    | sed 's/NUMERIC\([^\)]*\)/BIGINT UNSIGNED/g'
     | sed 's/CHECKSUM_BLOB_TYPE/VARBINARY\(200\)/g'
     > mysql_catalogue_schema.sql
   COMMAND cat