filer: default the filemeta CREATE TABLE for postgres2/mysql2 when createTable is unset (#10232)

* postgres2: default the filemeta CREATE TABLE when createTable is unset

An empty createTable rendered through fmt.Sprintf produced
%!(EXTRA string=filemeta), which Postgres rejected with a syntax error at
init. Fall back to a working template so a minimal config bootstraps.

* mysql2: default the filemeta CREATE TABLE when createTable is unset

Same empty-template failure the postgres2 path had: an unset createTable
rendered to %!(EXTRA string=filemeta) and MySQL rejected it at init.
Fall back to a working template.

weed/filer/postgres/postgres_sql_gen.go

@@ -20,6 +20,10 @@ type SqlGenPostgres struct {
 // user enables upsert but does not provide their own template.
 const DefaultUpsertQuery = `INSERT INTO "%s" (dirhash,name,directory,meta) VALUES($1,$2,$3,$4) ON CONFLICT (dirhash, name) DO UPDATE SET directory=EXCLUDED.directory, meta=EXCLUDED.meta`
 
+// DefaultCreateTableQuery is used when createTable is left unset; an empty
+// template would otherwise render as %!(EXTRA ...) garbage SQL.
+const DefaultCreateTableQuery = `CREATE TABLE IF NOT EXISTS "%s" (dirhash BIGINT, name VARCHAR(65535), directory VARCHAR(65535), meta bytea, PRIMARY KEY (dirhash, name))`
+
 var (
 	_ = abstract_sql.SqlGenerator(&SqlGenPostgres{})
 )

weed/filer/postgres/postgres_sql_gen_test.go

@@ -16,6 +16,17 @@ func TestDefaultUpsertQueryIsConflictSafe(t *testing.T) {
 	}
 }
 
+func TestDefaultCreateTableQueryRendersValidSql(t *testing.T) {
+	gen := &SqlGenPostgres{CreateTableSqlTemplate: DefaultCreateTableQuery}
+	got := gen.GetSqlCreateTable("filemeta")
+	if strings.Contains(got, "%!") {
+		t.Fatalf("template rendered to malformed SQL, got: %s", got)
+	}
+	if !strings.Contains(got, `"filemeta"`) {
+		t.Fatalf("expected quoted table name, got: %s", got)
+	}
+}
+
 func TestEmptyUpsertTemplateFallsBackToPlainInsert(t *testing.T) {
 	gen := &SqlGenPostgres{}
 	got := gen.GetSqlInsert("filemeta")