関連ワード:  sql where column is null or empty    sql where field is null or empty    sql where column is not null or empty    sql select where column is null or empty    sql server where column is null or empty    sql check column is null or empty    sql where field is not null or empty    sql select where column is not null or empty    sql check if column is null or empty in select statement    sql check if column is null or empty then 0