Database Programming

Attributes can be classified as identifiers or descriptors. Identifiers, more commonly called keys or key attributes uniquely identify an instance of an entity. If such an attribute doesn't exist naturally, a new attribute is defined for that purpose, for example an ID number or code. A descriptor describes a non-unique characteristic of an entity instance.

An entity usually has an attribute whose values are distinct for each individual entity. This attribute uniquely identifies the individual entity. Such an attribute is called a key attribute. For example, in the Employee entity type, EmpNo is the key attribute since no two employees can have same employee number. Similarly, for Product entity type, ProdId is the key attribute.

There may be a case when one single attribute is not sufficient to identify entities. Then a combination of attributes can solve this purpose. We can form a group of more than one attribute and use this combination as a key attribute. That is known as a composite key attribute. When identifying attributes of entities, identifying key attribute is very important.

a) Identify and describe FIVE characteristics of an efficient database

If your talking about phones I would say a blackberry

Working with mySQL databases:

<?php

// Connects to the database

mysql_connect(servername,username,password);

// Inserts into a database mysql_query(INSERT INTO table(cat1, cat2, cat3) VALUES(one,two,three)); ?>

Use OLE object. That is how mine works :)

First a single stage trigger. A single stage is the common type of trigger where you pull quite a ways until, at some point, the gun fires. A two-stage trigger eliminates that ambigious "some point" by adding a second stage to the pull. Basically, the trigger "catches" for lack of a better term (really it doesn't catch, it just encounters a greater resistance) towards the end of the pull. When you feel that resistance, you know that the next little bit of pull will fire the gun. One advantage of a two-stage trigger is that if you want a heavy trigger pull (like you would want for safety in law enforcement) it allows for this force to be broken up in two stages of the pull. This helps accuracy. For instance, with a 5 pound pull, you can put 3 pounds on the first stage and 2 on the second. You can aim, pull to the end of the first stage, then exhale, gently squeeze and BANG! Good fun, just like Iron City Blues.

1. More Complexity

2. More difficult to recover from a failure

3. More expensive

tables

BCNF, 3NF, 2NF, 1NF

Non First Normal Form

Both

A database is simply the data that has been stored in tables. A database management system includes all the elements that are required to work with the database. This would include things like the language to write queries, facilities for creating reports, controls over security and access of data and other elements.

select * from ( select eno, ename, sal, rank() over(order by sal desc) rnk ) where rnk = 3

quantified data can be used like this in research.

Example:

How old are you?

Answer:

a. 12

b. 23

c. 31

d. 45

e. 56

f. 70 and above

(this is used in a survey)

A.K.A you need a numerical data

You can save it in NUMERIC or varchar datatype.

Disadvantage of Data Base System:

1 Complexity in simplifying database

2. Cost

3. Time Consuming because extra burden over DBA.

level of a node in any binary tree can be calculated by summing up the number of nodes traversed from the root node of the tree to the node whose level has to be calculated!!!! dats it!!

if count is the no. of elements passed, then floor(log2(count-1)) is the level

An "Information Resource Analyst" sounds like a job title. It doesn't show up in a standard internet search.

So the best idea is to take a look at the job description.

If you take a look at the specific words, this title could refer to an information researcher or meta-researcher who specializes in finding information resources. Possibly a reference desk librarian.

An "analyst" is widely used and mis-used to mean ANY professional who is not a full-time computer programmer.

In terms of pure speculation, the job duties might look a lot like a Data Analyst or Business Intelligence Analyst.

The extensibility of the query architecture is used in the LINQ project itself to provide implementations that work over both XML and SQL data. The query operators over XML (LINQ to XML) use an efficient, easy-to-use, in-memory XML facility to provide XPath/XQuery functionality in the host programming language. The query operators over relational data (LINQ to SQL) build on the integration of SQL-based schema definitions into the common language runtime (CLR) type system. This integration provides strong typing over relational data while retaining the expressive power of the relational model and the performance of query evaluation directly in the underlying store.

I would say from a particle sense there is no real advantage. One could argue that a local database will not rely on connectivity (over the internet as an example) and therefore negate a possible failure point. The disadvantage is keeping each client side database in sync. Administration, programming, maintenance becomes nearly impossible. Security, data integrity, data and information theft. Data corruption which could be replicated if databases are to update other client systems.

i key field is a field with with a key in the middle :)

-128

* less likely to have a virus on the computer * less cable - so more cheaper