Merge pull request #325 from datafold/issue317

Better error messages in databases; Default database in clickhouse is now 'default'.

Author: erezsh

data_diff/__main__.py

@@ -307,15 +307,11 @@ def _main(
         )
         return
 
-    try:
-        db1 = connect(database1, threads1 or threads)
-        if database1 == database2:
-            db2 = db1
-        else:
-            db2 = connect(database2, threads2 or threads)
-    except Exception as e:
-        logging.error(e)
-        return
+    db1 = connect(database1, threads1 or threads)
+    if database1 == database2:
+        db2 = db1
+    else:
+        db2 = connect(database2, threads2 or threads)
 
     now: datetime = db1.query(current_timestamp(), datetime)
     now = now.replace(tzinfo=None)

data_diff/sqeleton/databases/clickhouse.py

@@ -23,6 +23,7 @@
 )
 from ..abcs.mixins import AbstractMixin_MD5, AbstractMixin_NormalizeValue
 
+DEFAULT_DATABASE = "default"    # https://clickhouse.com/docs/en/operations/server-configuration-parameters/settings/#default-database
 
 @import_helper("clickhouse")
 def import_clickhouse():
@@ -164,7 +165,7 @@ def __init__(self, *, thread_count: int, **kw):
 
         self._args = kw
         # In Clickhouse database and schema are the same
-        self.default_schema = kw["database"]
+        self.default_schema = kw.get("database", DEFAULT_DATABASE)
 
     def create_connection(self):
         clickhouse = import_clickhouse()

data_diff/sqeleton/databases/mysql.py

@@ -111,7 +111,10 @@ def __init__(self, *, thread_count, **kw):
         super().__init__(thread_count=thread_count)
 
         # In MySQL schema and database are synonymous
-        self.default_schema = kw["database"]
+        try:
+            self.default_schema = kw["database"]
+        except KeyError:
+            raise ValueError("MySQL URL must specify a database")
 
     def create_connection(self):
         mysql = import_mysql()