diff --git a/packages/db-meta-schema/deploy/schemas/collections_public/tables/field/table.sql b/packages/db-meta-schema/deploy/schemas/collections_public/tables/field/table.sql
index b1c973e9..c6905309 100644
--- a/packages/db-meta-schema/deploy/schemas/collections_public/tables/field/table.sql
+++ b/packages/db-meta-schema/deploy/schemas/collections_public/tables/field/table.sql
@@ -69,4 +69,11 @@ COMMENT ON CONSTRAINT db_fkey ON collections_public.field IS E'@omit manyToMany'
 CREATE INDEX field_table_id_idx ON collections_public.field ( table_id );
 CREATE INDEX field_database_id_idx ON collections_public.field ( database_id );
 
-COMMIT;
\ No newline at end of file
+-- Add AST column for SQL expression validation (AST is the source of truth)
+ALTER TABLE collections_public.field ADD COLUMN
+    default_value_ast jsonb NULL DEFAULT NULL;
+
+-- Smart comment for Graphile SQL expression validator plugin
+COMMENT ON COLUMN collections_public.field.default_value IS E'@sqlExpression';
+
+COMMIT;
diff --git a/packages/db-meta-schema/sql/db-meta-schema--0.15.3.sql b/packages/db-meta-schema/sql/db-meta-schema--0.15.3.sql
index 9c256d6a..2631dcbb 100644
--- a/packages/db-meta-schema/sql/db-meta-schema--0.15.3.sql
+++ b/packages/db-meta-schema/sql/db-meta-schema--0.15.3.sql
@@ -216,6 +216,11 @@ CREATE INDEX field_table_id_idx ON collections_public.field (table_id);
 
 CREATE INDEX field_database_id_idx ON collections_public.field (database_id);
 
+ALTER TABLE collections_public.field ADD COLUMN
+    default_value_ast jsonb NULL DEFAULT NULL;
+
+COMMENT ON COLUMN collections_public.field.default_value IS '@sqlExpression';
+
 CREATE UNIQUE INDEX databases_field_uniq_names_idx ON collections_public.field (table_id, (decode(md5(lower(regexp_replace(name, '^(.+?)(_row_id|_id|_uuid|_fk|_pk)$', E'\\1', 'i'))), 'hex')));
 
 CREATE TABLE collections_public.foreign_key_constraint (
@@ -867,4 +872,4 @@ CREATE INDEX site_themes_site_id_idx ON meta_public.site_themes (site_id);
 
 COMMENT ON CONSTRAINT db_fkey ON meta_public.site_themes IS '@omit manyToMany';
 
-CREATE INDEX site_themes_database_id_idx ON meta_public.site_themes (database_id);
\ No newline at end of file
+CREATE INDEX site_themes_database_id_idx ON meta_public.site_themes (database_id);