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MySQL foreign key constraints, cascade delete
...illed, then you've set up your foreign keys improperly. Given your example tables, you should have the following table setup:
CREATE TABLE categories (
id int unsigned not null primary key,
name VARCHAR(255) default null
)Engine=InnoDB;
CREATE TABLE products (
id int unsigned not null ...
Change type of varchar field to integer: “cannot be cast automatically to type integer”
I have a small table and a certain field contains the type " character varying ". I'm trying to change it to " Integer " but it gives an error that casting is not possible.
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Database sharding vs partitioning
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Partitioning is more a generic term for dividing data across tables or databases. Sharding is one specific type of partitioning, part of what is called horizontal partitioning.
Here you replicate the schema across (typically) multiple instances or servers, using some kind of logic or ...
Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
...g a little trouble understanding the pass-by-reference properties of data.table . Some operations seem to 'break' the reference, and I'd like to understand exactly what's happening.
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Why do Twitter Bootstrap tables always have 100% width?
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All tables within the bootstrap stretch according to their container, which you can easily do by placing your table inside a .span* grid element of your choice. If you wish to remove this property you can create your own table cl...
Copy rows from one Datatable to another DataTable?
How can I copy specific rows from DataTable to another Datable in c#? There will be more than one row.
11 Answers
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SQL Server - Create a copy of a database table and place it in the same database?
I have a table ABC in a database DB. I want to create copies of ABC with names ABC_1, ABC_2, ABC_3 in the same DB. How can I do that using either Management Studio (preferably) or SQL queries ?
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Delete all rows in an HTML table
How can I delete all rows of an HTML table except the <th> 's using Javascript, and without looping through all the rows in the table? I have a very huge table and I don't want to freeze the UI while I'm looping through the rows to delete them
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Altering column size in SQL Server
How to change the column size of the salary column in the employee table from numeric(18,0) to numeric(22,5)
6 Answe...
Difference between Hive internal tables and external tables?
Can anyone tell me the difference between Hive's external table and internal tables.
I know the difference comes when dropping the table. I don't understand what you mean by the data and metadata is deleted in internal and only metadata is deleted in external tables.
Can anyone explain me in terms o...