I'm adding a new column position to a table. This column should hold a unique value within all rows with the same userId. It doesn't really matter if they're ordered by id, creation or just randomly. For instance:
id userId time subn position created
1 1 33 FG 1 2016-08-13
2 1 57 FG 2 2016-08-15
3 1 20 XM 3 2016-08-11
4 2 81 FG 1 2016-08-01
5 3 12 FG 1 2016-08-27
6 3 33 FG 2 2016-08-18
How can I do this? I've tried creating a copy table (so that MySQL doesn't complain of target the target table for update being specified in from), setting the initial value to 0 and running this:
UPDATE userTimes_copy uic
SET position = (SELECT 1 + MAX(uic2.position)
FROM userTimes uic2
WHERE uic.userId = uic2.userId);
But it doesn't work. The first two rows, that have the same userId, get 486 (I have 485 rows) in position, and all of the rest 1.
I'm trying to normalize some data, and can't seem to come up with a solution. What I have is a table like this:
weight position1 position2 position3
1 10 20 30
2 25 35 45
3 17 05 22
and one like this:
location position
6 1
7 1
8 2
9 2
10 2
11 3
12 3
How do I normalize the above so that given a location and a weight, I can find the value for a given position?
I can use Perl, Python, Excel, MySQL or pretty much any tool on the block to do the actual reshuffling of the data; where I'm having a problem is in coming up with a reasonable schema.
The desired outcome here is something like
if location == 11 -> position is 3
therefore,
if weight == 2 -> the value is 45
The only thing to do is "unpivot" your first table to this:
weight position value
1 1 10
1 2 20
1 3 30
2 1 25
2 2 35
2 3 45
3 1 17
3 2 05
3 3 22
The first two columns should contain unique pairs of values. If you have other information that only depends on weight, you would need another table for that. Same for positions.
Converting to the new model
If you already have the tables, then you can create the first table (t1) with this statement:
create table t1_new
select weight, 1 as position, position1 as value
from t1
union all
select weight, 2 as position, position2 as value
from t1
union all
select weight, 3 as position, position3 as value
from t1
Then, after verification of the result, drop t1, and rename t1_new to t1.
Querying from the new model
To query from these tables the value for a given location and weight, you should use a join:
select value
from t1
inner join t2 on t2.weight = t1.weight
where t2.location = 11
and t1.position = 3
i have a table :
a b c
1 10 1001
7 6 54
56 2000 31
1200 5 9
4 10 20
2 65 20
how can i select rows with column's value of this row smaller than 1000. i want to get this
a b c
7 6 54
4 10 20
2 65 20
mysql query still get all value :
SELECT a,b,c FROM test
where a <'1000' or b<'1000' or c<'1000'
It sounds like you would like to pull a row where there is NO column greater than 1000 in that row, if that is correct then you need to us AND instead of OR.
SELECT a,b,c FROM test
where a <'1000' AND b<'1000' AND c<'1000'
Hope that helps!
So Here is My data
ID C1 C2 C3
6 Digit 2 6,8,10,12
12 Digit 3 15
15 127 Digit 2 6,7,8,9,10,11,12,13
68 140,141 Digit 11 85,86,87,88,167,168,158,159
73 1 Digit 11 85,86,87,88,169,170
76 Digit 11 85,86,87,91,164,165,166,167,168
99 Digit 11 20,27,85,86,87
106 Digit 1 1,2
111 Digit 11 85,86,87,88
112 Digit 11 85,86,87,88
135 Digit 11 85,86,87
and my condition string is (2,6,15,37,42,52,62,65,79,85,94,100,104,107,113,124,131)
Now,I want to exclude row 3,4,5 if the values 127,140,141,1 are not in the list condition. I tried Not in , but no avail. I think I might be missing something basic, but just cant get it.
It's better not to store multiple values in a column if possible. Then it's easier to do queries like this.
You cannot use "IN" or "NOT IN" because they are looking for a list of separate items. But C3 is just one item that happens to have commas in it.
Try this:
SELECT * FROM
(SELECT ID, C1, C2, CONCAT('|',REPLACE(C3,',','|'),'|') as C3 FROM `table` WHERE `C3` ) as t1
WHERE t1.C3 NOT LIKE "|127|" AND t1.C3 NOT LIKE "|140|" AND t1.C3 NOT LIKE "|141|" AND t1.C3 NOT LIKE "|1|"
You could avoid the "|" and just concat "," to the start and end.
Or you could fix your database schema so that it actually acts like a Normalized Relational Database.
Every column that contains multiple values should be separated out into its own table.
There should be no column C3 in your table above. Instead, you should have a table, some_other_data:
At this point, I see that C3=6 is related to more than one record in the main table. Therefore, you actually need a third, linking table, in addition to some_other_data. See below.
`some_other_data`
id
6
8
10
12
15
`main_table_to_some_other_data_link`
some_other_data_id | main_table_id
6 6
8 6
10 6
12 6
15 12
6 15
etc. You can see that the linking table can contain duplicates of either value. But your other two tables would have completely unique ids.
I think you're trying to solve the wrong problem.
(I'm assuming you can change your table structure. If you can't someone else will need to address your question.)
The long lists of comma-separated data are a flag that they have a one-to-many relationship with ID.
For example, make the data in C3 its own table:
ID MainID C3
================
1 6 6
2 6 8
3 6 10
4 6 12
5 12 15
6 15 6
7 15 7
8 15 8
9 15 9
10 15 10
11 15 11
12 15 12
13 15 13
// and so forth //
So ID is the primary key of the new table, MainID is the foreign key that refers to the record in your primary table, and C3 is the data in C3.
Each separate value of C3 now has its own record.
Now, you're in a position to use something like
Select * from MainTable
Inner Join NewTable
On MainTable.ID = NewTable.MainID
Where NewTable.C3 Not In (2,6,15,37,42,52,62,65,79,85,94,100,104,107,113,124,131);
If you can, pulling out the one-to-many relationships into their own tables will make things easier for you.
I have the table below
relID value charge
1 2 5
1 8 2
2 1 10
2 4 6
2 9 2
For the above table i need for a given value ex 10 to find what to charge for each relID
In the above for value<10 i need to get charge=5 for relID=1 and charge=2 for relID=2
I am trying to use 1 sql command to get it and i am kind of lost
Can anyony help
Thanks
Your question isn't very clear but I think this will work for you
SELECT t.relID,
(
SELECT charge
FROM table
WHERE relID = t.relID
AND value < 10
ORDER BY value
LIMIT 1
) AS charge
FROM table AS t
Let me rephrase.
Here is the table
relID value charge
1 2 5
1 8 2
2 1 10
2 4 6
2 9 2
Explain the table :
Lets say that the value and charge are money.
If the user has value 2 then i must charge with 5 using relID 1
If the user has value 8 then i must charge with 2 using relID 1
same for the relID 2
So when a user come with a value 10 i must find what to charge.So for the given value 10 i must find in the table all records with value<10.
In the example the values for value <10 are
For relID=1 are (2,8)
For relID=2 are (1,4,9)
Now for each relID i need to get the max value.
For relID=1 max value is 8 so charge is 2
For relID=2 max value is 9 so charge is 2
I plain english there are value rate
0-2 charge 5
2-8 charge 2
and ...
i hope to be clear now
select *
from Table t
where value =
(select max(value)
from Table
where value <= 10
and relId = t.relId)