Merge pull request #71 from ydb-platform/float_double_sa_14

Use YDB Double for sa Float for compat with 1.4 old dialect

Author: vgvoleg

ydb_sqlalchemy/sqlalchemy/compiler/sa14.py

@@ -1,3 +1,7 @@
+from typing import Union
+import sqlalchemy as sa
+import ydb
+
 from .base import (
     BaseYqlCompiler,
     BaseYqlDDLCompiler,
@@ -7,7 +11,23 @@
 
 
 class YqlTypeCompiler(BaseYqlTypeCompiler):
-    ...
+    # We use YDB Double for sa.Float for compatibility with old dialect version
+    def visit_FLOAT(self, type_: sa.FLOAT, **kw):
+        return "DOUBLE"
+
+    def get_ydb_type(
+        self, type_: sa.types.TypeEngine, is_optional: bool
+    ) -> Union[ydb.PrimitiveType, ydb.AbstractTypeBuilder]:
+        if isinstance(type_, sa.TypeDecorator):
+            type_ = type_.impl
+
+        if isinstance(type_, sa.Float):
+            ydb_type = ydb.PrimitiveType.Double
+            if is_optional:
+                return ydb.OptionalType(ydb_type)
+            return ydb_type
+
+        return super().get_ydb_type(type_, is_optional)
 
 
 class YqlIdentifierPreparer(BaseYqlIdentifierPreparer):