[英]Fetching Latest Record from MySQL for each individual
我有一張這樣的桌子
╔════╦════════╦═════════════╦═════════════════╗
║ PK ║ NAME ║ DEGREE ║ YEAR_OF_PASSING ║
╠════╬════════╬═════════════╬═════════════════╣
║ 1 ║ Shrey ║ B.E. ║ 2004 ║
║ 2 ║ Shrey ║ High School ║ 2000 ║
║ 3 ║ Gaurav ║ B.E. ║ 2000 ║
║ 4 ║ Gaurav ║ M.Sc. ║ 2002 ║
╚════╩════════╩═════════════╩═════════════════╝
如何查詢獲取每個人最新學位的結果集,如下所示?
╔════╦════════╦════════╦═════════════════╗
║ PK ║ NAME ║ DEGREE ║ YEAR_OF_PASSING ║
╠════╬════════╬════════╬═════════════════╣
║ 1 ║ Shrey ║ B.E. ║ 2004 ║
║ 4 ║ Gaurav ║ M.Sc. ║ 2002 ║
╚════╩════════╩════════╩═════════════════╝
SELECT a.*
FROM tableName a
INNER JOIN
(
SELECT Name, MAX(Year_Of_Passing) max_val
FROM tableName
GROUP BY Name
) b ON a.name = b.name AND
a.Year_Of_Passing = b.max_val
更新1
SELECT a.*
FROM tableName a
INNER JOIN
(
SELECT Name, MAX(Year_Of_Passing) max_val, MAX(PK) max_pk
FROM tableName
GROUP BY Name
) b ON a.name = b.name AND
CASE WHEN b.max_val IS NULL
THEN a.pk = max_PK
ELSE a.Year_Of_Passing = b.max_val
END
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