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How to sum a variable by group
...he syntax behind each alternative. For instance, if I have a larger source table and want to subselect just two dimensions plus summed metrics, can I adapt any of these methods? Hard to tell.
– Dodecaphone
Oct 28 '18 at 10:42
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MySQL case insensitive select
...in did mention collate was better) We had historical data moved into mysql table which broke legacy logic because of certain column values having insensitive case. We needed to know the difference between "GE1234" and "ge1234", they needed to be unique and stay logged that way. We set our column in ...
How do I drop a foreign key constraint only if it exists in sql server?
I can drop a table if it exists using the following code but do not know how to do the same with a constraint:
10 Answers
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Delete duplicate records in SQL Server?
Consider a column named EmployeeName table Employee . The goal is to delete repeated records, based on the EmployeeName field.
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Efficiently convert rows to columns in sql server
...Code, LastName, AccountNumber
from
(
select value, columnname
from yourtable
) d
pivot
(
max(value)
for columnname in (Firstname, Amount, PostalCode, LastName, AccountNumber)
) piv;
See Demo.
Pivot with unknown number of columnnames
If you have an unknown number of columnnames that you w...
Calculate a Running Total in SQL Server
Imagine the following table (called TestTable ):
15 Answers
15
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Querying data by joining two tables in two database on different servers
There are two tables in two different databases on different servers, I need to join them so as to make few queries. What options do I have? What should I do?
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SQL Server dynamic PIVOT query?
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Dynamic SQL PIVOT:
create table temp
(
date datetime,
category varchar(3),
amount money
)
insert into temp values ('1/1/2012', 'ABC', 1000.00)
insert into temp values ('2/1/2012', 'DEF', 500.00)
insert into temp values ('2/1/2012', 'GHI',...
Center image in table td in CSS
I've been trying to align an image to the center of the table td. It worked with setting margin-left to a specific value but it also increased the size of td too and that isn't exactly what I wanted
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Facebook database design?
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Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
Emai...