Add new backend capabilities for the extension

edb/pgsql/metaschema.py

@@ -5115,7 +5115,10 @@ async def create_pg_extensions(
     commands.add_command(
         dbops.CreateSchema(name=ext_schema, conditional=True),
     )
-    for ext in ["uuid-ossp", "edb_stat_statements"]:
+    extensions = ["uuid-ossp"]
+    if backend_params.has_stat_statements:
+        extensions.append("edb_stat_statements")
+    for ext in extensions:
         if (
             inst_params.existing_exts is None
             or inst_params.existing_exts.get(ext) is None

edb/pgsql/params.py

@@ -40,6 +40,8 @@ class BackendCapabilities(enum.IntFlag):
     CREATE_ROLE = 1 << 3
     #: Whether CREATE DATABASE is allowed
     CREATE_DATABASE = 1 << 4
+    #: Whether extension "edb_stat_statements" is available
+    STAT_STATEMENTS = 1 << 5
 
 
 ALL_BACKEND_CAPABILITIES = (
@@ -48,6 +50,7 @@ class BackendCapabilities(enum.IntFlag):
     | BackendCapabilities.C_UTF8_LOCALE
     | BackendCapabilities.CREATE_ROLE
     | BackendCapabilities.CREATE_DATABASE
+    | BackendCapabilities.STAT_STATEMENTS
 )
 
 
@@ -111,6 +114,13 @@ def has_create_database(self) -> bool:
             & BackendCapabilities.CREATE_DATABASE
         )
 
+    @property
+    def has_stat_statements(self) -> bool:
+        return bool(
+            self.instance_params.capabilities
+            & BackendCapabilities.STAT_STATEMENTS
+        )
+
 
 @functools.lru_cache
 def get_default_runtime_params(

edb/server/pgcluster.py

@@ -1170,6 +1170,13 @@ async def _detect_capabilities(
         if roles['rolcreatedb']:
             caps |= pgparams.BackendCapabilities.CREATE_DATABASE
 
+        stats_ver = await conn.sql_fetch_val(b"""
+            SELECT default_version FROM pg_available_extensions
+            WHERE name = 'edb_stat_statements';
+        """)
+        if stats_ver in (b"1.0",):
+            caps |= pgparams.BackendCapabilities.STAT_STATEMENTS
+
         return caps
 
     async def _get_pg_settings(