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Topic: Non-standard grouping of the data in request

Good afternoon!
Help to fulfill request about grouping of the data please:
There is a table distancetime (id, time, name), the following data is written to it:
1 3:10:00 AM Punkt1
2 3:17:00 AM Punkt1
3 3:18:00 AM Punkt1
4 3:29:00 AM Punkt2
5 3:40:00 AM Punkt3
6 3:42:00 AM Punkt3
7 3:52:00 AM Punkt1
8 3:53:00 AM Punkt1
9 3:54:00 AM Punkt4
10 5:25:00 AM Punkt5
As a result of request should it turns out:
1 3:10:00 AM Punkt1
4 3:29:00 AM Punkt2
5 3:40:00 AM Punkt3
7 3:52:00 AM Punkt1
9 3:54:00 AM Punkt4
10 5:25:00 AM Punkt5
Prompt please as the given sampling can be carried out.

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Re: Non-standard grouping of the data in request

Well if you still tell, HOW from the initial data total sampling why these records are left is received, and remaining are discarded...

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Re: Non-standard grouping of the data in request

Akina wrote:

Well if you still tell, HOW from the initial data total sampling why these records are left is received, and remaining are discarded...

I assume that there should be a check on entrances of Points, i.e. 1stroka-time of Punkt1, further, if the name changed an output 4stroka-time of Punkt2, then by analogy 5stroka-time of Punkt3, further a name changed 7stroka-time of Punkt1 and .
How to carry out the given check (grouping) inside Select to me it is not clear. Therefore also I ask helps
If to carry out sampling on unique entrances repeating entrances on Points, through various time intervals disappear

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Re: Non-standard grouping of the data in request

SELECT id, ` time `, name
FROM (SELECT (name! = @prev) ok, (@prev: = name) name, id, ` time`
FROM distancetime, (SELECT @prev: = ") x
ORDER BY ` time`
) xx
WHERE ok;

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Re: Non-standard grouping of the data in request

Akina wrote:

SELECT id, ` time `, name
FROM (SELECT (name! = @prev) ok, (@prev: = name) name, id, ` time`
FROM distancetime, (SELECT @prev: = ") x
ORDER BY ` time`
) xx
WHERE ok;

Thanks big! I will know now!