May 25, 2023 · May 11, 2023 · May 11, 2023 · May 11, 2023 · May 12, 2023 · May 12, 2023
diff --git a/src/databricks/sqlalchemy/dialect/__init__.py b/src/databricks/sqlalchemy/dialect/__init__.py
    supports_multivalues_insert: bool = True
    supports_native_decimal: bool = True
    supports_sane_rowcount: bool = False
    supports_comments: bool = True

    @classmethod
    def dbapi(cls):
                "nullable": bool(col.NULLABLE),
                "default": col.COLUMN_DEF,
                "autoincrement": False if col.IS_AUTO_INCREMENT == "NO" else True,
                'comment': col.REMARKS,
            }
            columns.append(this_column)


    def get_table_names(self, connection, schema=None, **kwargs):
        TABLE_NAME = 1
        catalog = "`" + self.catalog + "`"
        schema = ("`" + schema + "`") or ("`" + self.schema + "`")

        with self.get_driver_connection(
            connection
        )._dbapi_connection.dbapi_connection.cursor() as cur:
            sql_str = "SHOW TABLES FROM {}".format(
                ".".join([self.catalog,schema or self.schema])
                ".".join([catalog, schema])
            )
            data = cur.execute(sql_str).fetchall()
            _tables = [i[TABLE_NAME] for i in data]
diff --git a/src/databricks/sqlalchemy/dialect/base.py b/src/databricks/sqlalchemy/dialect/base.py
 import re
 from sqlalchemy.sql import compiler
 from sqlalchemy.sql import compiler, sqltypes, ColumnElement


 class DatabricksIdentifierPreparer(compiler.IdentifierPreparer):
 class DatabricksDDLCompiler(compiler.DDLCompiler):
    def post_create_table(self, table):
        return " USING DELTA"

    def visit_set_column_comment(self, create, **kw):
        """
        Example syntax for adding column comment:
        "ALTER TABLE schema.table_name CHANGE COLUMN COLUMN_NAME COMMENT 'Comment to be added to column';"

        """
        return """ALTER TABLE {0} CHANGE COLUMN {1} COMMENT {2}""".format(
            self._format_table_from_column(
                 create, use_schema=True
            ),
            self.preparer.format_column(
                create.element, use_table=False
            ),
            self.sql_compiler.render_literal_value(
                create.element.comment, sqltypes.String()
            ),
        )

    def visit_drop_column_comment(self, drop, **kw):
        """
        Example syntax for dropping column comment:
        "ALTER TABLE schema.table_name CHANGE COLUMN COLUMN_NAME COMMENT '';"

        Note: There is no syntactical 'DROP' statement in this case, the comment must be replaced with an empty string
        """
        return "ALTER TABLE {0} CHANGE COLUMN {1} COMMENT '';".format(
            self._format_table_from_column(
                 drop, use_schema=True
            ),
            self.preparer.format_column(
                drop.element, use_table=False
            )
        )

    def _format_table_from_column(self, column_object, use_schema=False):
        """
        Prepare a quoted table name from the column object (including schema if specified)
        """
        schema_table_column = self.preparer.format_column(
                column_object.element, use_table=True, use_schema=True
            )

        name = schema_table_column.split(".")[1]

        if use_schema:
            name = schema_table_column.split(".")[0] + '.' + name

        return name
Original file line number	Diff line number	Diff line change
Expand Up		@@ -80,6 +80,7 @@ class DatabricksDialect(default.DefaultDialect):
		supports_multivalues_insert: bool = True
		supports_native_decimal: bool = True
		supports_sane_rowcount: bool = False
		supports_comments: bool = True

		@classmethod
		def dbapi(cls):
Expand DownExpand Up		@@ -174,6 +175,7 @@ def get_columns(self, connection, table_name, schema=None, **kwargs):
		"nullable": bool(col.NULLABLE),
		"default": col.COLUMN_DEF,
		"autoincrement": False if col.IS_AUTO_INCREMENT == "NO" else True,
		'comment': col.REMARKS,
		}
		columns.append(this_column)

Expand DownExpand Up		@@ -244,11 +246,14 @@ def get_indexes(self, connection, table_name, schema=None, **kw):

		def get_table_names(self, connection, schema=None, **kwargs):
		TABLE_NAME = 1
		catalog = "`" + self.catalog + "`"
		schema = ("`" + schema + "`") or ("`" + self.schema + "`")

		with self.get_driver_connection(
		connection
		)._dbapi_connection.dbapi_connection.cursor() as cur:
		sql_str = "SHOW TABLES FROM {}".format(
		".".join([self.catalog,schema or self.schema])
		".".join([catalog, schema])
		)
		data = cur.execute(sql_str).fetchall()
		_tables = [i[TABLE_NAME] for i in data]
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -1,5 +1,5 @@
		import re
		from sqlalchemy.sql import compiler
		from sqlalchemy.sql import compiler, sqltypes, ColumnElement


		class DatabricksIdentifierPreparer(compiler.IdentifierPreparer):
Expand All		@@ -15,3 +15,52 @@ def __init__(self, dialect):
		class DatabricksDDLCompiler(compiler.DDLCompiler):
		def post_create_table(self, table):
		return " USING DELTA"

		def visit_set_column_comment(self, create, **kw):
		"""
		Example syntax for adding column comment:
		"ALTER TABLE schema.table_name CHANGE COLUMN COLUMN_NAME COMMENT 'Comment to be added to column';"

		"""
		return """ALTER TABLE {0} CHANGE COLUMN {1} COMMENT {2}""".format(
		self._format_table_from_column(
		create, use_schema=True
		),
		self.preparer.format_column(
		create.element, use_table=False
		),
		self.sql_compiler.render_literal_value(
		create.element.comment, sqltypes.String()
		),
		)

		def visit_drop_column_comment(self, drop, **kw):
		"""
		Example syntax for dropping column comment:
		"ALTER TABLE schema.table_name CHANGE COLUMN COLUMN_NAME COMMENT '';"

		Note: There is no syntactical 'DROP' statement in this case, the comment must be replaced with an empty string
		"""
		return "ALTER TABLE {0} CHANGE COLUMN {1} COMMENT '';".format(
		self._format_table_from_column(
		drop, use_schema=True
		),
		self.preparer.format_column(
		drop.element, use_table=False
		)
		)

		def _format_table_from_column(self, column_object, use_schema=False):
		"""
		Prepare a quoted table name from the column object (including schema if specified)
		"""
		schema_table_column = self.preparer.format_column(
		column_object.element, use_table=True, use_schema=True
		)

		name = schema_table_column.split(".")[1]

		if use_schema:
		name = schema_table_column.split(".")[0] + '.' + name

		return name