#240: Enhanced schema.column_type.ColumnType

Author: ckunki

doc/changes/unreleased.md

@@ -3,3 +3,7 @@
 ## Documentation
 
 * #283: Updated description and README
+
+## Refactorings
+
+* #240: Enhanced `schema.column_type.ColumnType`

exasol/analytics/schema/column_type.py

@@ -23,16 +23,29 @@ class SizeUnit(Enum):
 class ColumnType:
     name: str
     precision: Optional[int] = None
+    """For column types DECIMAL and INTEGER."""
     scale: Optional[int] = None
+    """For column types DECIMAL and INTEGER."""
     size: Optional[int] = None
+    """For column types CHAR and VARCHAR."""
     characterSet: Optional[str] = None
+    """For column types CHAR and VARCHAR. Supported values: "ASCII" and "UTF8"."""
     withLocalTimeZone: Optional[bool] = None
+    """Only for column type TIMESTAMP."""
     fraction: Optional[int] = None
+    """Number of fractional seconds for column type TIMESTAMP."""
     srid: Optional[int] = None
+    """Spatial reference system identifier, only for column type GEOMETRY."""
     unit: Optional[SizeUnit] = None
+    """Only for column type HASHTYPE. Supported values: "BYTE" and "BIT"."""
 
     @property
     def rendered(self) -> str:
+        """
+        Return a string representing the type including all parameters
+        such as scale or precision appropriate for creating an SQL statement
+        CREATE TABLE.
+        """
         name = self.name.upper()
 
         def args() -> Iterator[Any]:
@@ -57,6 +70,8 @@ def elements() -> Iterator[str]:
                 yield f"({infix})"
             if name == "VARCHAR":
                 yield f' {self.characterSet or "UTF8"}'
+            if (name == "TIMESTAMP") and self.withLocalTimeZone:
+                yield " WITH LOCAL TIME ZONE"
 
         return "".join(elements())
 

tests/unit_tests/data_science_utils/schema/test_column_type.py

@@ -242,6 +242,8 @@ def test_hash_inequality_table():
         (ColumnType("DECIMAL", scale=2), "DECIMAL"),
         (ColumnType("TIMESTAMP"), "TIMESTAMP"),
         (ColumnType("TIMESTAMP", precision=2), "TIMESTAMP(2)"),
+        (ColumnType("TIMESTAMP", precision=2, withLocalTimeZone=True),
+         "TIMESTAMP(2) WITH LOCAL TIME ZONE"),
         (ColumnType("HASHTYPE"), "HASHTYPE(16 BYTE)"),
         (ColumnType("HASHTYPE", size=10), "HASHTYPE(16 BYTE)"),
         (ColumnType("HASHTYPE", unit=SizeUnit.BIT), "HASHTYPE(16 BYTE)"),