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What is the difference between HAVING and WHERE in SQL?
What is the difference between HAVING and WHERE in an SQL SELECT statement?
20 Answers
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Finding duplicate rows in SQL Server
...abase of organizations, and there are many duplicate rows. I want to run a select statement to grab all of these and the amount of dupes, but also return the ids that are associated with each organization.
...
NOT IN vs NOT EXISTS
...llow NULLs the NOT IN will be treated identically to the following query.
SELECT ProductID,
ProductName
FROM Products p
WHERE NOT EXISTS (SELECT *
FROM [Order Details] od
WHERE p.ProductId = od.ProductId)
The exact plan may vary but for my examp...
Difference between “read commited” and “repeatable read”
...nd consider you have a simple task like the following:
BEGIN TRANSACTION;
SELECT * FROM T;
WAITFOR DELAY '00:01:00'
SELECT * FROM T;
COMMIT;
That is a simple task that issue two reads from table T, with a delay of 1 minute between them.
under READ COMMITTED, the second SELECT may return any da...
JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
...
How to drop all user tables?
...
BEGIN
FOR cur_rec IN (SELECT object_name, object_type
FROM user_objects
WHERE object_type IN
('TABLE',
'VIEW',
'MATERIAL...
Correct way to use StringBuilder in SQL
...:
StringBuilder sb = new StringBuilder(some_appropriate_size);
sb.append("select id1, ");
sb.append(id2);
sb.append(" from ");
sb.append(table);
return sb.toString();
Note that I've listed some_appropriate_size in the StringBuilder constructor, so that it starts out with enough capacity for the f...
SQL select only rows with max value on a column [duplicate]
...ce...
All you need is a GROUP BY clause with the MAX aggregate function:
SELECT id, MAX(rev)
FROM YourTable
GROUP BY id
It's never that simple, is it?
I just noticed you need the content column as well.
This is a very common question in SQL: find the whole data for the row with some max value ...
What are DDL and DML?
...als with data
manipulation, and includes most common SQL statements such SELECT,
INSERT, UPDATE, DELETE etc, and it is used to store, modify, retrieve,
delete and update data in database.
SELECT – retrieve data from the a database
INSERT – insert data into a table
UPDATE – up...
Highlight all occurrence of a selected word?
How can I highlight all occurrence of a selected word in GVim, like in Notepad++?
15 Answers
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