MCP: A few updates about JDBC and CrateDB nightly re. current_database

Author: amotl

framework/mcp/backlog.md

@@ -3,10 +3,6 @@
 ## Iteration +1
 - Builtin: Submit a CrateDB adapter, getting rid of the
   `Could not roll back transaction: error`
-- JDBC: Tool `list_tables` currently blocks.
-- JDBC: Tool `describe_table` does not work.
-  Problem with `SELECT current_database()`.
-  https://github.com/crate/crate/issues/17393
 - DBHub: Reading resource `tables` does not work,
   because `WHERE table_schema = 'public'`
 - PG-MCP: Improve installation after packaging has been improved.

framework/mcp/example_jdbc.py

@@ -38,8 +38,7 @@ async def run():
 
             # Call a few tools.
             await client.call_tool("database_info")
-            # FIXME: This operation currently blocks.
-            # await client.call_tool("list_tables", arguments={})
+            await client.call_tool("list_tables")
             await client.call_tool("describe_table", arguments={"schema": "sys", "table": "summits"})
             await client.call_tool("read_query", arguments={"query": "SELECT * FROM sys.summits ORDER BY height DESC LIMIT 3"})
             await client.call_tool("create_table", arguments={"query": "CREATE TABLE IF NOT EXISTS testdrive.mcp_jdbc (id INT, data TEXT)"})

framework/mcp/test.py

@@ -69,10 +69,10 @@ def test_jdbc():
     assert b"Calling tool: database_info" in p.stdout
     assert b"database_product_name: PostgreSQL" in p.stdout
     assert b"driver_name: PostgreSQL JDBC Driver" in p.stdout
+    assert b"Calling tool: list_tables" in p.stdout
+    assert b'TABLE_NAME: jobs_log' in p.stdout
     assert b"Calling tool: describe_table" in p.stdout
-    # FIXME: Problem with `SELECT current_database()`.
-    #        https://github.com/crate/crate/issues/17393
-    assert b"Failed to describe table: The column name current_database was not found in this ResultSet." in p.stdout
+    assert b'coordinates' in p.stdout
     assert b"Calling tool: read_query" in p.stdout
     assert b'mountain: Mont Blanc' in p.stdout