如果您确定列名正确，那么问题可能出在连接顺序上。听起来逗号的每一侧的连接都是单独构建的。（我不确定这是否可能，但是这是我根据您提供的信息做出的唯一猜测）
该查询可以重组为：
SELECt`PuzzleCategories`.`PuzzleCategory`,`Clients`.`BusinessName`,`Puzzles`.`PuzzleNumber`FROM`Clients`INNER JOIN `Publications` ON `Clients`.`ClientID` = `Publications`.`ClientID`INNER JOIN `PublicationIssues` ON `PublicationIssues`.`PublicationID` = `Publications`.`PublicationID`INNER JOIN `PuzzleUsages` ON`PuzzleUsages`.`PublicationIssueID` = `PublicationIssues`.`PublicationIssueID`INNER JOIN `Puzzles` ON `Puzzles`.`PuzzleID` = `PuzzleUsages`.`PuzzleID`INNER JOIN `PuzzleCategories` ON `Puzzles`.`PuzzleCategoryID` = `PuzzleCategories`.`PuzzleCategoryID`
反正读起来更好。
