Mysql 如何将返回多个记录的查询更改为返回包含原始记录串联的单个记录?
我不太喜欢数据库,我面临以下问题。我正在使用MySql 我有一个疑问:Mysql 如何将返回多个记录的查询更改为返回包含原始记录串联的单个记录?,mysql,sql,database,rdbms,Mysql,Sql,Database,Rdbms,我不太喜欢数据库,我面临以下问题。我正在使用MySql 我有一个疑问: SELECT LSSN.livestock_species_name AS species_name, LSFT.feed_type_name AS feed_type_name, LSFT.description AS feed_description FROM LivestockDetails AS LSD INNER JOIN Li
SELECT
LSSN.livestock_species_name AS species_name,
LSFT.feed_type_name AS feed_type_name,
LSFT.description AS feed_description
FROM LivestockDetails AS LSD
INNER JOIN LivestockSpecies AS LSS
ON LSD.live_stock_species_id = LSS.id
INNER JOIN LivestockSpeciesName AS LSSN
ON LSS.id = LSSN.livestock_species_id
INNER JOIN Languages AS LNG
ON LSSN.language_id = LNG.id
INNER JOIN LsFeedDetails AS LSFD
ON LSD.ls_feed_details_id = LSFD.id
INNER JOIN LsFeedTypes AS LSFT
ON LSFD.ls_feed_types_id = LSFT.id
WHERE LSD.live_stock_species_id = 3
AND LSD.ls_area_id = 2
AND LSD.ls_action_type_id = 1
AND LSD.ls_message_id is null
AND LNG.id = 1
返回这些记录:
species_name feed_type_name feed_description
-----------------------------------------------------------------------------------------------------------------------------------------------------------------
Local Cows Rangeland Grasses
Local Cows Crop residues Maize and sorghum Stover, rice, wheat, and sugar bean straw, parts of banana plants, wheat straw
Local Cows Improved grasses e.g. Napier grass
Local Cows Browsing and herbaceous legumes Browsing (largely during dry season) and herbaceous legumes (year round)
Local Cows Planted pastures Napier, etc...
Local Cows Assorted weeds Assorted weeds
好的,这些检索到的数据很好,但我必须修改此查询,以便:
1) 它返回一条记录,其中包含前一个查询检索到的记录中包含的所有信息的串联
2) 连接必须如下所示:
feed_type_name RECORD-1 + (feed_description RECORD-1) + ";" +feed_type_name RECORD-2 + (feed_description RECORD-2) + ";" + feed_type_name RECORD-3 + ";" + (feed_description RECORD-3) + ..............................
Rangeland (Grasses) ; Crop residues (Maize and sorghum Stover, rice, wheat, and sugar bean straw, parts of banana plants, wheat straw) ; Improved grasses (e.g. Napier grass) ; ............................................
因此,使用前面检索到的数据作为示例如下:
feed_type_name RECORD-1 + (feed_description RECORD-1) + ";" +feed_type_name RECORD-2 + (feed_description RECORD-2) + ";" + feed_type_name RECORD-3 + ";" + (feed_description RECORD-3) + ..............................
Rangeland (Grasses) ; Crop residues (Maize and sorghum Stover, rice, wheat, and sugar bean straw, parts of banana plants, wheat straw) ; Improved grasses (e.g. Napier grass) ; ............................................
我真的不知道如何修改我的原始查询来创建这样的查询。你能帮我做吗?按“物种名称”分组,并使用GROUP CONCAT(饲料类型名称分隔符“,”)功能
按“物种名称”分组,并使用GROUP CONCAT(饲料类型名称分隔符“,”)功能
使用
分组,并使用分组:
SELECT
LSSN.livestock_species_name AS species_name,
GROUP_CONCAT(CONCAT(LSFT.feed_type_name, ' (', LSFT.description, ')') SEPARATOR ';') AS text
FROM LivestockDetails AS LSD
INNER JOIN LivestockSpecies AS LSS
ON LSD.live_stock_species_id = LSS.id
INNER JOIN LivestockSpeciesName AS LSSN
ON LSS.id = LSSN.livestock_species_id
INNER JOIN Languages AS LNG
ON LSSN.language_id = LNG.id
INNER JOIN LsFeedDetails AS LSFD
ON LSD.ls_feed_details_id = LSFD.id
INNER JOIN LsFeedTypes AS LSFT
ON LSFD.ls_feed_types_id = LSFT.id
WHERE
LSD.live_stock_species_id = 3
AND LSD.ls_area_id = 2
AND LSD.ls_action_type_id = 1
AND LSD.ls_message_id is null
AND LNG.id = 1
GROUP BY
LSSN.livestock_species_name;
使用GROUP_CONCAT
并使用GROUP by
按物种聚集:
SELECT
LSSN.livestock_species_name AS species_name,
GROUP_CONCAT(CONCAT(LSFT.feed_type_name, ' (', LSFT.description, ')') SEPARATOR ';') AS text
FROM LivestockDetails AS LSD
INNER JOIN LivestockSpecies AS LSS
ON LSD.live_stock_species_id = LSS.id
INNER JOIN LivestockSpeciesName AS LSSN
ON LSS.id = LSSN.livestock_species_id
INNER JOIN Languages AS LNG
ON LSSN.language_id = LNG.id
INNER JOIN LsFeedDetails AS LSFD
ON LSD.ls_feed_details_id = LSFD.id
INNER JOIN LsFeedTypes AS LSFT
ON LSFD.ls_feed_types_id = LSFT.id
WHERE
LSD.live_stock_species_id = 3
AND LSD.ls_area_id = 2
AND LSD.ls_action_type_id = 1
AND LSD.ls_message_id is null
AND LNG.id = 1
GROUP BY
LSSN.livestock_species_name;
可以按如下方式进行
SELECT feed_type_name +'('+feed_description +') ; ' as [text()] from
.....
.....
.....
FOR XML PATH('')
可以按如下方式进行
SELECT feed_type_name +'('+feed_description +') ; ' as [text()] from
.....
.....
.....
FOR XML PATH('')
OP使用的是MySQL,而不是SQL Server。OP使用的是MySQL,而不是SQL Server。