我有以下观点：
CREATE VIEW FilmTableView AS
SELECT (TitleSP || " / " || TitleEN) as Title,CompanyName,CoverURI,CompanyFilmRelation.CompanyId,CompanyFilmRelation.FilmId
FROM Film
JOIN CompanyFilmRelation on CompanyFilmRelation.FilmId = Film.FilmId
JOIN Company on CompanyFilmRelation.CompanyId = Company.CompanyId
ORDER BY Title;
但我最终可能会得到TitleSP或TitleEN为空的记录.在这种情况下,我只想包含哪个列不为null而不包含“/”.
有没有办法做到这一点？也就是说,遵循以下逻辑：
if(TitleSP && TitleEN) select (TitleSP || " / " || TitleEN) as Title else select (TitleSP ? TitleSP : TitleEn) as Title
解决方法
SELECT CASE WHEN (TitleSP = '' OR TitleSP IS NULL)
THEN COALESCE(TitleEN,'')
WHEN (TitleEN = '' OR TitleEN IS NULL)
THEN TitleSP
ELSE (TitleSP || ' / ' || TitleEN)
END AS Title,...
