text: #ifndef SQL_DB_CACHE_H
  #define SQL_DB_CACHE_H
  
  struct sql_db_cache;
  
  /* Like sql_init(), but use a connection pool. */
  struct sql_db *
  sql_db_cache_new(struct sql_db_cache *cache,
  		 const char *db_driver, const char *connect_string);
  
  struct sql_db_cache *sql_db_cache_init(unsigned int max_unused_connections);
  void sql_db_cache_deinit(struct sql_db_cache **cache);
  
  #endif
  