Fix: handle empty models exists (#993)

Author: tobymao

setup.py

@@ -44,7 +44,7 @@
         "requests",
         "rich",
         "ruamel.yaml",
-        "sqlglot~=16.1.0",
+        "sqlglot~=16.1.2",
         "fsspec",
     ],
     extras_require={

sqlmesh/core/state_sync/engine_adapter.py

@@ -241,6 +241,11 @@ def snapshots_exist(self, snapshot_ids: t.Iterable[SnapshotIdLike]) -> t.Set[Sna
         }
 
     def models_exist(self, names: t.Iterable[str], exclude_external: bool = False) -> t.Set[str]:
+        names = set(names)
+
+        if not names:
+            return names
+
         query = (
             exp.select("name")
             .from_(self.snapshots_table)