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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...
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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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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How to get the last N records in mongodb?
... order mixed up ... your sort() should be run last, not first (much like a SQL ORDER BY) .find({}).skip(1).limit(50).sort({"date":-1})
– Justin Jenkins
Mar 6 '12 at 19:11
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How do I create a PDO parameterized query with a LIKE statement?
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thanks. had similar issue with csharp + Mysql + ODBC using like it would not return any rows using "select * from table where column like '%?%';" but will if I do like you did "select * from table where column like ?;" and set the parameter string so: string frag = $...
Hibernate throws org.hibernate.AnnotationException: No identifier specified for entity: com..domain.
...otations on it whatsoever - leave it a simple pojo.
Update: In regards to SQL views, Hibernate docs write:
There is no difference between a view and a base table for a Hibernate mapping. This is transparent at the database level
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MySQL vs MySQLi when using PHP [closed]
Which is better, MySQL or MySQLi? And why? Which should I use?
6 Answers
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Are there disadvantages to using a generic varchar(255) for all text-based fields?
...ld always store 255 characters.
But since you tagged this question with MySQL, I'll mention a MySQL-specific tip: as rows are copied from the storage engine layer to the SQL layer, VARCHAR fields are converted to CHAR to gain the advantage of working with fixed-width rows. So the strings in memor...
PostgreSQL “DESCRIBE TABLE”
How do you perform the equivalent of Oracle's DESCRIBE TABLE in PostgreSQL (using the psql command)?
22 Answers
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Best way to check for “empty or null value”
What is best way to check if value is null or empty string in Postgres sql statements?
10 Answers
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