Hello, Do the clustered and non-clustered indexes both work on B-Tree? I read that clustered indexes affect the way how the data is physically stored in table whereas with non-clustered indexes a separate copy of the column is created and that is stored in sorted order. Also, Sql Server creates clustered indexes on primary key by defaul...
Why RDBMS? data integrity get quality results with SQL and prevent duplicates use SQL to access the data --> Easy. Many more Why Key-value pair? horizontally scalable Simple datasets - hashmap, associative arrays etc Easy to put() and get() Many more. So, is there some kind of wrapper available which binds with the "nosql" kind o...
I recently realized that I add some form of row creation timestamp and possibly a "updated on" field to most of my tables. Suddenly I started thinking that perhaps every table in the database should have a created and modified field that are set in the model behind the scenes. Does this sound correct? Are there any types of high-load ta...
I was reading a book and it talks about a User has some more UserDetail, and so the UserDetail will have a user_id pointing back to the Users table. I kind of forgot that, does it help at all to has a field in Users table to have a user_detail_id to point at the UserDetail record? This is so in Ruby on Rails too, that the Users table d...
In designing RDBMS schema, I wonder if there is formal principle of concrete objects: for example, if it is Persons table, then each record is very concrete and unique. Each record in fact represents a unique person. But what about a table such as Courses (as in school). It can have a description, number of units, offered only in Autu...
Simple question, could I conceivably use redis instead of mysql for all sorts of web applications: social networks, geo-location services etc? ...
I have a large table with 10+ millions records in a SQL Server database. The table contains certain type of data for all 50 states in the US. So if I create 50 views, one for each state, from this table, would the performance of making queries from my application be improved? Other suggestions? ...
For example, if we are doing Analytics recording the page_type, item_id, date, pageviews, timeOnPage. It seems that they are several ways to avoid it. Is there an automatic way? create index on the fields that uniquely identify the record, for example [page_type, item_id, date] and make the index unique, so that when adding the sam...
Inserting null into not null column with default is giving me a validation error instead of taking the default value. I don't want to make on before triggers to all of the tables. Is there any other way to do this? Firebird 2.1.3 ...
I am using ARCH Linux and Awesome3 WM. I am looking for a good sql client for multi database include mysql postgre oracal. Squirrel sql seems good, but I got a blank window after launch it. Any solution for this problem or there is another better client for me? ...
I have the following db-schema . FILE, GROUP and BLOCK represent the object structure of the XML file. FILE is the root. GROUP has FK to FILE. BLOCK has the one FK to GROUP and the another one FK to UNIT. UNIT groups "similar" BLOCKs from diffrent GROUPs in the context of FILE. The data base is currently in 3NF. Yet I would like ...
Hi, I Am trying to learn the RDBMS. I have question for you guys. Why does a DBMS interleave the actions of the different transactions instead of executing transactions one after another? ...
I'm making a site to document browser bugs where users can submit a bug and users can submit solutions/workarounds to these bugs. I'll have stuff like: screenshots of bugs browser rendering engines browsers tags for each bug bug categories ( css, html, js ) solutions per bug which include code snippets usual date/time, author, date mod...
I think with SQLite3, at least it doesn't keep any cached page because there is no server and each write will exit SQLite3, so it can't do any caching directly. But when it is MySQL, Postgresql, or MongoDB, there will be a layer which, when the data is thought to be saved already, it is actually in the memory cache of the DBMS... to be ...
I think one of the advantages of no-sql such as MongoDB is that it can scale horizontally automatically: just add a cheap machine and the data can "spread over" to the new machine. How about for RDBMS, does any RDBMS do that automatically too? ...
Hi everyone. Searched google for "firebird update duplicates" and "firebird handle duplicate update" but did not get any stuff, that would solve my question; so i thought it would be a good idea to use this marvellous site for the first time :) So how do i achieve mysql's "INSERT INTO asdf (x,y,z) VALUES ('a',1,2) ON DUPLICATE KEYS UPDA...
I have a table containing roles. Many users can be assigned to a role. Permissions can be assigned to a role, granting all users to that role with the permission. When I assign a permission to a role that has 500 hundred people, I've effectively created 500 permission assignments. With each permission that is assigned to a role I spe...
I have a table Users (simplified) : UserId (int, PK) | Username | PasswordHash | LastVisitTimestamp Every time user visits a web site, LastVisitTimestamp column is updated. Is it a good idea to move that column into a separate table, so that timestamp updates do not lock entire row (actual row is bigger than presented here). I did...
I'm curious as to what the major pros/cons are of using an object relational database over a regular relational database are? In what circumstances is it more practical, and are object relational databases the future? ...
Our application supports SQL Server and Oracle as database backend. During investigation stuff database tuning advisor on SQL Server suggested to create an index on table which resulted significant improvement of query execution time against this table. I'd like to try to create the same index on oracle but a problem with understanding ...