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Hide/Show Column in an HTML Table
I have an HTML table with several columns and I need to implement a column chooser using jquery. When a user clicks on a checkbox I want to hide/show the corresponding column in the table. I would like to do this without attaching a class to every td in the table, is there a way to select an entir...
MySQL - why not index every field?
...n called), so it could potentially slow read operations as well (for large tables).
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DROP IF EXISTS VS DROP?
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Standard SQL syntax is
DROP TABLE table_name;
IF EXISTS is not standard; different platforms might support it with different syntax, or not support it at all. In PostgreSQL, the syntax is
DROP TABLE IF EXISTS table_name;
The first one will throw an...
How can I let a table's body scroll but keep its head fixed in place?
I am writing a page where I need an HTML table to maintain a set size. I need the headers at the top of the table to stay there at all times but I also need the body of the table to scroll no matter how many rows are added to the table. Think a mini version of excel. This seems like a simple task bu...
Permission denied for relation
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GRANT on the database is not what you need. Grant on the tables directly.
Granting privileges on the database mostly is used to grant or revoke connect privileges. This allows you to specify who may do stuff in the database if they have sufficient other permissions.
You want ins...
Get list of databases from SQL Server
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@Gia It does exist as a backwards compatablity view. msdn.microsoft.com/en-us/library/ms179900%28v=SQL.110%29.aspx
– Chris Diver
Aug 7 '11 at 22:26
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What are the performance characteristics of sqlite with very large database files? [closed]
...application).
The tests involve a single sqlite file with either a single table, or multiple tables. Each table had about 8 columns, almost all integers, and 4 indices.
The idea was to insert enough data until sqlite files were about 50GB.
Single Table
I tried to insert multiple rows into a sqli...
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 ...
Extracting bits with a single multiplication
...K bits of a 64-bit integer. These lower K bits can then be used to index a table of pre-computed bitboards that representst the allowed squares that the piece on its origin square can actually move to (taking care of blocking pieces etc.)
A typical chess engine using this approach has 2 tables (on...
Table overflowing outside of div
I'm trying to stop a table that has width explicitly declared from overflowing outside of its parent div . I presume I can do this in some way using max-width , but I can't seem to get this working.
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