I have a table of items, each of it has an a_level, b_level, and an item_id. Any b_level is dedicated to only one a_level (example: b_level 14 is \"child\" of a_level 2 only)
As I understand, an index on a typical database table will provide a more efficient row look up. Does a similar construct exist for making queries with aggregate functions more efficient?
I have a query that gets generated (by Django) like this: SELECT `geo_ip`.`id`, `geo_ip`.`start_ip`, `geo_ip`.`end_ip`, `geo_ip`.`start`,
I have a query that does this: SELECT `threaded_comments`.* FROM `threaded_comments` WHERE `threaded_comments`.`parent_id` IN (4, 5)
Say, we have something like this: add_column :users, :single, :boolean add_index :users, :single and then later we do
Is there some tool that does this? You give it a SQL query and it gives suggestions. For example, I\'m trying to optimize the following query:
Environment: Rails 3.0.4, MySQL, Ruby 1.8.7 I have the following table: create_table \"countries\", :force => true do |t|
We currently have a query in our app like this: SELECT * FROM combos WHERE text = \'[text]\' We\'re putting a category_id column on combos, and the query will change to this:
I\'m using Firebird 2.1 and I\'m looking for the best way to solve this issue. I\'m writing a calendaring application. Different users\' calendar entries are stored in a big Calendar table. Each cale
What I mean is: Does a table with 20 columns benefit more from indexing a certain field (one that\'s used in search-ish queries) than a table that has just 4 columns?
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