For example, the table has columns MYINDEX and NAME.
MYINDEX | NAME
=================
1 | BOB
2 | BOB开发者_运维知识库
3 | CHARLES
Ho do I find row with highest MYINDEX for specific NAME? E.g. I want to find ROW-2 for name "BOB".
SELECT Max(MYINDEX) FROM table WHERE NAME = [insertNameHere]
EDIT: to get the whole row:
Select * //never do this really
From Table
Where MYINDEX = (Select Max(MYINDEX) From Table Where Name = [InsertNameHere]
There are several ways to tackle this one. I'm assuming that there may be other columns that you want from the row, otherwise as others have said, simply name, MAX(my_index) ... GROUP BY name
will work. Here are a couple of examples:
SELECT
MT.name,
MT.my_index
FROM
(
SELECT
name,
MAX(my_index) AS max_my_index
FROM
My_Table
GROUP BY
name
) SQ
INNER JOIN My_Table MT ON
MT.name = SQ.name AND
MT.my_index = SQ.max_my_index
Another possible solution:
SELECT
MT1.name,
MT1.my_index
FROM
My_Table MT1
WHERE
NOT EXISTS
(
SELECT *
FROM
My_Table MT2
WHERE
MT2.name = MT1.name AND
MT2.my_index > MT1.my_index
)
SELECT MAX(MYINDEX) FROM table
WHERE NAME = 'BOB'
For the whole row, do:
SELECT * FROM table
WHERE NAME = 'BOB'
AND MyIndex = (SELECT Max(MYINDEX) from table WHERE NAME = 'BOB')
If you wanted to see the highest index for name = 'Bob', use:
SELECT MAX(MYINDEX) AS [MaxIndex]
FROM myTable
WHERE Name = 'Bob'
If you want to skip the inner join, you could do:
SELECT * FROM table WHERE NAME = 'BOB' ORDER BY MYINDEX DESC LIMIT 1;
Use
FROM TABLE SELECT MAX(MYINDEX), NAME GROUP BY NAME
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