When william b. campbell (u) is the successor what is the district?
CREATE TABLE table_2147588_4 (district VARCHAR, successor VARCHAR)
SELECT district FROM table_2147588_4 WHERE successor = "William B. Campbell (U)"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_2147588_4 (district VARCHAR, successor VARCHAR) Question: When william b. campbell (u) is the successor what is the district? [/INST] SELECT district FROM table_2147588_4 WHERE successor = "William B. Campbell (U)" </s>