All Questions
28 questions
0
votes
1
answer
171
views
Overlaying rows in SQL
So, I want to store sets of key-value pairs in a database and then retrieve a combined set of the key-value pairs based on a series of sets. Each set might not be complete.
Let's say we have a table ...
- 740
1
vote
2
answers
173
views
How to verify if DB remote server is running using only java raw sockets [Telnet]
I wanted to explore an option to write minimal code to check if db2 server is running using plain java sockets. Just like doing telnet to server. It seems db2 is not configured to respond for telnet ...
1
vote
2
answers
91
views
Is it really needed to define a column as foreign key in all tables where it is used
I have a users table which has user_id as primary key and it is used in other 40 to 50 tables(approx.).
Is it necessary to define user_id column as foreign key in each and every table where user_id is ...
- 184
0
votes
1
answer
235
views
Developing a comprehensive set of SQL statements/queries based on Sakila or other standard database [closed]
I'm developing a comprehensive set of SQL statements/queries based on Sakila or other standard database.
I'm testing a number of DB Connectivity Drivers, against different DBs (i.e. MySQL, Oracle, ...
- 301
1
vote
2
answers
73
views
Select single row with multiple rows in joined table
I have a contact table as below:
contactid | contactname
----------|-------------
C1 | Name1
C2 | Name2
I have a communication table as below
contactid | communication_type | ...
- 19
-4
votes
2
answers
70
views
Select from two tables joid vs Joining two Selects
I always see people use these two ways for joining two or more tables.
select *
from BOOKS as B
where B.name = 'GOOD BOOK'
inner join select *
from AUTHOR as A
where A.AUTHOR_NAME = 'GOOD AUTHOR' on ...
- 3
-2
votes
2
answers
237
views
query to obtain final status as fail when any one of listed subject is failed
Select count(course),course,dept,
Case
When ****condition*** then 'passed'
Else 'failed'
End as finalstatus
from college group by course,dept;
Here condition should check each subject of each ...
- 117
0
votes
3
answers
83
views
Subquery Issue while fetching the columns from 3 tables
I have 3 tables x,y,z
x has username, fullname
y has username, comm, time
z has fusername, musername
I want to select x.fullname, x.username, y.comm, y.time
where the inner joined fields are x....
- 1
0
votes
1
answer
70
views
sql query for n rows plus another a row with id
I have a query, which return (say)10 rows
SELECT EL.ID AS ID ,EL.x AS x ,EL.y AS y,EL.z AS z,
EL.k AS k, EL.a AS a,
EL.b AS b ,EL.c AS c,EL.d AS d ,EL.e AS e ,
...
- 113
-1
votes
2
answers
132
views
How to set the maximum disk size of a database MySQL, Oracle, PostGreSQL or DB2? [closed]
This is how I do in SQL Server:
Create Database MyDatabase
on (Name='MyDatabase_Data',
Filename='c:\db\BdUnisanta_Data.mdf',
Size= 20MB,
FileGrowth = 10%,
Maxsize=100MB)
log on
(...
- 99
1
vote
4
answers
6k
views
Compare table content with external file- SQL
I have an Excel file with users IDs, called users Excel.
In the Database I have a users table: this table holds the data from the users excel file and from another file (administrators file).
I ...
- 2,661
0
votes
1
answer
279
views
How can I achieve unicode normal form C with collation in MySQL, db2, Derby or Oracle databases?
I have tried using different collation methods across different implementations of SQL databases, but am unable to achieve complete normalization. Does anyone have any tips for this in any of the ...
- 561
0
votes
2
answers
147
views
Converting between clause to joins [duplicate]
Need a generic sql query for joins that can run on mysql, postgres and other major DBs
I have a table named autumn4.ip , I have three columns: id,start,end (all ints).
How do I make a join so that I ...
- 741
7
votes
2
answers
1k
views
Which DBMS's allow an order by of an attribute, that is not present in the select clause?
Let's assume I have a table called Cars with 2 columns: CarName, BrandName
Now I want to execute this query:
select CarName
from Cars
order by BrandName
As you can see, I'd like to return a list, ...
- 19.4k
2
votes
4
answers
1k
views
Insert query based on number of rows
I want a query to insert a row into a table I know it is simple but the scenario is the table should not have more than 5 rows. If table has more than five rows I need to remove the old row(Or replace ...
- 493