I have table which consist of 35,000 records in which half of the rows have name as null value
If the field has null value, i want to update the field with the value of username.
Can anyone help me with this ?
This is sample table
name | username | idnumber | type
----------------------------------------------
-- | jack | 1 | A
Mark | Mark | 2 | B
-- | dev | 3 | A
After update i want it to look like this
name | username | idnumber | type
----------------------------------------------
jack | jack | 1 | A
Mark | Mark | 2 | B
dev | dev | 3 | A
You seem to want:
update t
set name = username
where name is null;
Note that -- is not a typical representation of NULL values. You might consider <null> for instance.
Related
I have an enum State which can contain values like CA, NY, etc.
If I have a table Users , with a column states that contains an array of State values, so for example {CA, NY} how can I write a query to count the users grouped by each State value? so for {CA, NY} that should count 1 for CA and 1 for NY
So If I had records like:
| id | states |
| -- | ------- |
| 1 | {CA,NY} |
| 2 | {CA} |
| 3 | {NV,CA} |
I would expect a query to output:
| State | count |
| ----- | ----- |
| CA | 3 |
| NV | 1 |
| NY | 1 |
The first piece of advice is to normalise your data. You are breaking 2nd Normal form by holding multiple pieces of information in a single column.
Assuming you can't change that, then you will need to SPLIT the data like this
enter link description here
and you can then COUNT() and group it.
I have an issue with converting a varchar column filled with id's (foreign keys) to another string with names, these names are linked in another table with their correlating id.
Data
x-----x------------------------x
| Id | foreign Keys (varchar) |
x-----x------------------------x
| 1 | 1,2,3 |
| 2 | 2,3,4 |
| 3 | 4 |
x-----x------------------------x
Names
x-----x-----------------x
| Id | Names (varchar)|
x-----x-----------------x
| 1 | Rick |
| 2 | Steven |
| 3 | Charly |
| 4 | Tom |
x-----x-----------------x
Basically I need the values in the table data to UPDATE to a varchar like 'Rick, Steven, Charly'.
I am working in SQL Server 2014, so I can't use the function STRING_SPLIT.
Help would be really appreciated
Thanks
What I mean is the following.
I have a database containing people. These people van a name and a role.
It looks like this:
-----------------------------
| (PK) id | name | role |
-----------------------------
| 1 | ben | fireman |
| 2 | ron | cook |
| 3 | chris | coach |
| 4 | remco | barber |
-----------------------------
Ive created a searchbar where you can search for people in the database. When you press search, it looks for name and roles, for example:
When I type in 'co', the result I get is:
-----------------------------
| (PK) id | name | role |
-----------------------------
| 3 | chris | coach |
| 4 | remco | barber |
| 2 | ron | cook |
-----------------------------
This is because its looking for matches in the name and role column.
The query I use is:
SELECT * FROM people WHERE name LIKE '$search' OR role LIKE '$search' ORDER BY name";
The only issue with this is that it just order by name.
I want it to first order every result from the name column by name and then order every remaining result from the role column by name, so it ends up looking like this:
-----------------------------
| (PK) id | name | role |
-----------------------------
| 4 | remco | barber | <- 'co' found in name column, ordered by name
| 3 | chris | coach | <- 'co' found in role column, ordered by name
| 2 | ron | cook | <- 'co' found in role column, ordered by name
-----------------------------
How can I do this?
Edit: $search is the output from the searchbar
Use a case expression to put the 'co' names first:
order by case when name LIKE '$search' then 0 else 1 end, name, role
I have a table in which several indentifiers of a person may be stored. In this table I would like to create a single calculated identifier column that stores the best identifier for that record depending on what identifiers are available.
For example (some fictional sample data) ....
Table = "Citizens"
Id | LastName | DL-No | SS-No | State-Id-No | Calculated
------------------------------------------------------------------------
1 | Smith | NULL | 374-784-8888 | 7383204848 | ?
2 | Jones | JG892435262 | NULL | NULL | ?
3 | Trask | TSK73948379 | NULL | 9276542119 | ?
4 | Clinton | CL231429888 | 543-123-5555 | 1840430324 | ?
I know the order in which I would like choose identifiers ...
Drivers-License-No
Social-Security-No
State-Id-No
So I would like the calculated identifier column to be part of the table schema. The desired results would be ...
Id | LastName | DL-No | SS-No | State-Id-No | Calculated
------------------------------------------------------------------------
1 | Smith | NULL | 374-784-8888 | 7383204848 | 374-784-8888
2 | Jones | JG892435262 | NULL | 4537409273 | JG892435262
3 | Trask | NULL | NULL | 9276542119 | 9276542119
4 | Clinton | CL231429888 | 543-123-5555 | 1840430324 | CL231429888
IS this possible? If so what SQL would I use to calculate what goes in the "Calculated" column?
I was thinking of something like ..
SELECT
CASE
WHEN ([DL-No] is NOT NULL) THEN [DL-No]
WHEN ([SS-No] is NOT NULL) THEN [SS-No]
WHEN ([State-Id-No] is NOT NULL) THEN [State-Id-No]
AS "Calculated"
END
FROM Citizens
The easiest solution is to use coalesce():
select c.*,
coalesce([DL-No], [SS-No], [State-ID-No]) as calculated
from citizens c
However, I think your case statement will also work, if you fix the syntax to use when rather than where.
I have a table with information like this.
ID | Name | #ofCow | UItem | place
--------+---------+-------- +---------+----------
0 | Bob | 7 | 1 | maine
1 | Bob | 3 | 5 | new york
2 | Tom | 2 | 5 | cali
I wish to produce a table like this where it would add up the number of cows and Uitem if the name is the same. However my select query seems to not be working. I suspect it is because the place column is the problem. Since you can't add 'Maine' and 'New York' together. Can anyone help me find a solution ?
ID | Name | #ofCow | UItem |
--------+---------+-------- +---------+
0 | Bob | 10 | 6 |
2 | Tom | 2 | 5 |
TLDR : Add the values in two columns in table 1 if name is same. Output in another column. Don't show the two columns. I don't need places also.
You could use this (I have considered the name of the table as HolyCow) :
SELECT holy.ID,
holy.Name,
SUM(holy.Cows) as '#ofCow',
SUM(holy.UItem) as 'UItem'
FROM HolyCow holy
GROUP BY holy.ID, holy.Name
ORDER BY holy.Name
Hope this helps!!