具有标准的问题:
“ >>
提供有关创建满足此条件的SELECT语句的任何帮助。我认为正在使用的表如下。
CREATE TABLE `client` ( `ClientID` varchar(7) NOT NULL, `ClientName` varchar(45) DEFAULT NULL, `Street` varchar(100) DEFAULT NULL, `City` varchar(45) DEFAULT NULL, `State` char(2) DEFAULT NULL, `Zip` char(5) DEFAULT NULL, PRIMARY KEY (`ClientID`) ) CREATE TABLE `contact` ( `ClientID` varchar(7) NOT NULL, `ContactName` varchar(45) NOT NULL, `ContactPhone` char(17) DEFAULT NULL, `ContactEmail` varchar(45) DEFAULT NULL, PRIMARY KEY (`ClientID`,`ContactName`), CONSTRAINT `FK_ClientContact` FOREIGN KEY (`ClientID`) REFERENCES `client` (`ClientID`) )
这是我到目前为止所拥有的。
SELECT ClientName, contact.ContactName, ContactPhone, ContactEmail, count() FROM client, contact GROUP BY ClientName, ContactName, ContactPhone, ContactEmail ORDER BY ClientName;
附加信息:
CREATE TABLE `event_contact` (
`ClientID` varchar(7) NOT NULL,
`ContactName` varchar(45) NOT NULL,
`EventCode` varchar(12) NOT NULL,
PRIMARY KEY (`ClientID`,`ContactName`,`EventCode`),
KEY `FK_EC_Event_idx` (`EventCode`),
CONSTRAINT `FK_EC_Contact` FOREIGN KEY (`ClientID`, `ContactName`) REFERENCES `contact` (`ClientID`, `ContactName`),
CONSTRAINT `FK_EC_Event` FOREIGN KEY (`EventCode`) REFERENCES `events` (`EventCode`)
)
CREATE TABLE `events` (
`EventCode` varchar(12) NOT NULL,
`EventName` varchar(45) NOT NULL,
`Description` varchar(150) DEFAULT NULL,
`EventDate` date DEFAULT NULL,
`StartTime` time DEFAULT NULL,
`EndTime` time DEFAULT NULL,
`Ticket` tinyint(4) DEFAULT NULL,
`VenueID` char(7) NOT NULL,
`ClientID` varchar(7) NOT NULL,
PRIMARY KEY (`EventCode`),
KEY `FK_Events_Venue_idx` (`ClientID`),
KEY `FK_Events_Venue` (`VenueID`),
CONSTRAINT `FK_Events_Client` FOREIGN KEY (`ClientID`) REFERENCES `client` (`ClientID`),
CONSTRAINT `FK_Events_Venue` FOREIGN KEY (`VenueID`) REFERENCES `venue` (`VenueID`)
)
具有标准的问题:创建满足此标准的SELECT语句的任何帮助将不胜感激。我认为正在使用的表格如下。创建表`client`(...
此查询将列出每个客户的联系人的详细信息: