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MySQL “NOT IN” query
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NOT IN vs. NOT EXISTS vs. LEFT JOIN / IS NULL in MySQL
MySQL, as well as all other systems except SQL Server, is able to optimize LEFT JOIN / IS NULL to return FALSE as soon the matching value is found, and it is the only system that cared to document this behavior.
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Access denied for user 'test'@'localhost' (using password: YES) except root user
I am facing problem with mysql non root/admin user, I am following the below steps for creating user and its privileges, correct me if i am doing wrong,
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Generate a random number in the range 1 - 10
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If you are using SQL Server then correct way to get integer is
SELECT Cast(RAND()*(b-a)+a as int);
Where
'b' is the upper limit
'a' is lower limit
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What is “the inverse side of the association” in a bidirectional JPA OneToMany/ManyToOne association
...customer. So the customer seems to be the owner of the orders.
But in the SQL world, one item will actually contain a pointer to the other. Since there is 1 customer for N orders, each order contains a foreign key to the customer it belongs to. This is the "connection" and this means the order "own...
Reorder / reset auto increment primary key
I have a MySQL table with an auto increment primary key. I deleted some rows in the middle of the table. Now I have, for example, something like this in the ID column: 12, 13, 14, 19, 20. I deleted the 15, 16, 17 and 18 rows.
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Easiest way to copy a table from one database to another?
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If you have shell access you may use mysqldump to dump the content of database1.table1 and pipe it to mysql to database2. The problem here is that table1 is still table1.
mysqldump --user=user1 --password=password1 database1 table1 \
| mysql --user=user2 --passwo...
MySQL foreign key constraints, cascade delete
... When creating the tables, you need to specify InnoDB or another MySQL engine that's capable of CASCADE operations. Otherwise the MySQL default, MyISAM, will be used and MyISAM does not support CASCADE operations. To do this, just add ENGINE InnoDB before the last ;.
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What does it mean by select 1 from table?
...n the EXISTS is ignored and you can write this as per Page 191 of the ANSI SQL 1992 Standard:
SELECT * FROM AnotherTable
WHERE EXISTS (SELECT 1/0 FROM table WHERE...)
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Checking for a null int value from a Java ResultSet
...worth a separate thread on SO imho. (java.sun.com/j2se/1.4.2/docs/api/java/sql/…)
– Roman
May 27 '10 at 10:58
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MySQL with Node.js
... into Node.js. I come from a PHP background, so I'm fairly used to using MySQL for all my database needs.
9 Answers
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