You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: util.rs
    path of file: ./repos/libsql/libsql-sqlite3/ext/crr/rs/core/src
    
    the code of the file until where you have to start completion: extern crate alloc;

use crate::{alloc::string::ToString, tableinfo::ColumnInfo};
use alloc::format;
use alloc::string::String;
us
    
    fn test_get_db_version_union_query() {
        let tbl_names = vec!["foo".to_string(), "bar".to_string(), "baz".to_string()];
        let union = get_db_version_union_query(&tbl_names);
        assert_eq!(
            union,
            "SELECT max(version) as version FROM (SELECT max(db_version) as version FROM \"foo\" UNION ALL SELECT max(db_version) as version FROM \"bar\" UNION ALL SELECT max(db_version) as version FROM \"baz\" UNION SELECT value as\n        version FROM crsql_master WHERE key = 'pre_compact_dbversion')"
        );
    }