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SQL “select where not in subquery” returns no results
...MySQL
There are three ways to do such a query:
LEFT JOIN / IS NULL:
SELECT *
FROM common
LEFT JOIN
table1 t1
ON t1.common_id = common.common_id
WHERE t1.common_id IS NULL
NOT EXISTS:
SELECT *
FROM common
WHERE NOT EXISTS
(
SELECT NULL
FROM ...
SQL WHERE condition is not equal to?
... clause may be negated according to the above rules. The negation of this
select *
from foo
where test-1
and test-2
and ( test-3
OR test-4
)
is
select *
from foo
where NOT( test-1
and test-2
and ( test-3
OR te...
Parse JSON in TSQL
...ing
The article and code is here: Consuming Json strings in SQL server.
Select * from parseJSON('{
"Person":
{
"firstName": "John",
"lastName": "Smith",
"age": 25,
"Address":
{
"streetAddress":"21 2nd Street",
"city":"New York",
"state":"NY",
...
Why is it bad style to `rescue Exception => e` in Ruby?
...IFT-ESC), go to the "processes" tab, find your process, right click it and select "End process".
If you are working with someone else's program which is, for whatever reason, peppered with these ignore-exception blocks, then putting this at the top of the mainline is one possible cop-out:
%W/INT Q...
What's the difference between session.Merge and session.SaveOrUpdate?
...e.class);
configuration.setProperty("connection.driver_class","com.mysql.jdbc.Driver");
configuration.setProperty("hibernate.connection.url", "jdbc:mysql://localhost:3306/hibernate");
configuration.setProperty("hibernate.connection.username", "...
What does it mean when MySQL is in the state “Sending data”?
...
In this state:
The thread is reading and processing rows for a
SELECT statement, and sending data to the client.
Because operations occurring during this this state tend to perform
large amounts of disk access (reads).
That's why it takes more time to complete and so is the lon...
Can a C++ enum class have methods?
...
A union is not what John Doe would consider a class, too. Yet they can have member functions. And classes are really not mandatory for member functions. Using a designator like value or this, something like enum Size { Huge, Me...
Deleting rows with MySQL LEFT JOIN
...
DELETE FROM deadline where ID IN (
SELECT d.ID FROM `deadline` d LEFT JOIN `job` ON deadline.job_id = job.job_id WHERE `status` = 'szamlazva' OR `status` = 'szamlazhato' OR `status` = 'fizetve' OR `status` = 'szallitva' OR `status` = 'storno');
I am not sur...
Oracle取前N条记录方法 Oracle实现SELECT TOP N的方法 - 数据库(内核) - 清...
Oracle取前N条记录方法 Oracle实现SELECT TOP N的方法select * from ( select * from tablexxx order by xxx desc ) where rownum <= Noracle数据库不支持mysql中limit, top功...select * from ( select * from tablexxx order by xxx desc ) where rownum <= N
oracle数据库不支持mysql中li...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...and re-try where necessary.
Some attempted solutions also fail to consider SELECT races. If you try the obvious and simple:
-- THIS IS WRONG. DO NOT COPY IT. It's an EXAMPLE.
BEGIN;
UPDATE testtable
SET somedata = 'blah'
WHERE id = 2;
-- Remember, this is WRONG. Do NOT COPY IT.
INSERT INTO testt...