02 Database Systems PART1 — Transcript

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1. 0:02good day welcome to another topic
2. 0:04entitled database systems
3. 0:06again this is dr mary jane zamonte from
4. 0:08mapua university philippines
5. 0:10organizations use data to keep track of
6. 0:13their day-to-day operations
7. 0:15such data is used to generate
8. 0:17information which in turn
9. 0:19is the basis for good decisions data is
10. 0:22likely to be managed most efficiently
11. 0:24when it is stored in a database in this
12. 0:28chapter
13. 0:28you will learn what a database is what
14. 0:31it does
15. 0:32and why it yields better results than
16. 0:35other data management methods
17. 0:37you will also learn about various types
18. 0:39of databases
19. 0:40and why databases design is so important
20. 0:43so let's begin
21. 0:51so why do we need databases in today's
22. 0:54world
23. 0:54data is ubiquitous from birth to death
24. 0:58we generate and consume data also it is
25. 1:01pervasive
26. 1:02the trail of data starts with the birth
27. 1:03certificate and continues all the way to
28. 1:06a death certificate
29. 1:07and beyond databases make data
30. 1:10persistent and shareable
31. 1:12in a secure way data is not only
32. 1:14ubiquitous and pervasive
33. 1:16it is also essential for organizations
34. 1:18to survive
35. 1:19and prosper all businesses have to keep
36. 1:21this type of data and much more
37. 1:24at the heart of all the systems are the
38. 1:26collection storage
39. 1:27aggregation manipulation dissemination
40. 1:31and management of data
41. 1:36virtually all modern visa systems rely
42. 1:39on databases
43. 1:41therefore a good understanding of how
44. 1:43these structures are created
45. 1:45in their proper uses vital to understand
46. 1:48what drives database design you must
47. 1:51understand the difference between
48. 1:52data and information data
49. 1:56consists of row facts the word raw
50. 1:59indicates that the facts have not yet
51. 2:01been processed
52. 2:02to reveal their meaning information is
53. 2:06the result
54. 2:06of processing raw data to reveal its
55. 2:09meaning
56. 2:10data processing can be as simple as
57. 2:12organizing data to reveal
58. 2:15patterns are as complex as making
59. 2:17forecasts
60. 2:18or drawing inferences using statistical
61. 2:21modelling
62. 2:22to reveal meaning information requires
63. 2:26context for example an average
64. 2:29temperature reading of 105 degrees
65. 2:31does not mean much unless you also know
66. 2:35its context is this reading in degrees
67. 2:38fahrenheit
68. 2:39or celsius is this a machine temperature
69. 2:42a body temperature or an outside air
70. 2:45temperature
71. 2:46information can be used as the
72. 2:48foundation for decision making
73. 2:55efficient data management typically
74. 2:57requires the use of a computer database
75. 3:00a database is a shared integrated
76. 3:02computer structure
77. 3:04that stores a collection of the
78. 3:05following end user data
79. 3:08it is row facts of interest to the end
80. 3:11user
81. 3:12metadata or data about data through
82. 3:15which the end user data
83. 3:16is integrated in manage the metadata
84. 3:19describes
85. 3:20the data characteristics and the set of
86. 3:22relationships
87. 3:24that links the data found within the
88. 3:26database
89. 3:27which presents a more complete picture
90. 3:29of the data
91. 3:30in the database itself for example
92. 3:33the metadata component stores
93. 3:35information such as the name of each
94. 3:37data element
95. 3:38the type of values and whether the data
96. 3:42element can be left empty
97. 3:44given this characteristics of metadata
98. 3:48it is a database that describes as a
99. 3:50collection of self-describing data
100. 3:53a database management system or dbms
101. 3:56is a collection of programs that manages
102. 3:59the database
103. 4:00structure and controls access to the
104. 4:02data stored in the database
105. 4:04in a sense a database assembles a very
106. 4:07well organized
107. 4:08electronic filing cabinet in which
108. 4:11powerful software
109. 4:12helps manage the cabinet's contents
110. 4:19the bbms serves as the intermediary
111. 4:23between the user in the database the
112. 4:25database structure itself
113. 4:27is stored as a collection of files and
114. 4:30the only way to access the data in those
115. 4:32files is through the dbms
116. 4:35it enables data to be shared presents
117. 4:37the end user with an integrated view of
118. 4:39data
119. 4:41provides more efficient and effective
120. 4:43data management
121. 4:44and improves sharing security
122. 4:47integration access decision making
123. 4:50productivity and many more figure 1.4
124. 4:57emphasizes the point that the dbms
125. 4:59presents the end user
126. 5:01or application program with a single
127. 5:03integrated view of the data
128. 5:05in the database the dbms receives all
129. 5:08application requests
130. 5:10and translates them into the context
131. 5:12operations required to fulfill those
132. 5:14requests
133. 5:16the dbms hides much of the databases
134. 5:19internal complexity from the application
135. 5:22programs and users
136. 5:23the application program might be written
137. 5:25by a programmer
138. 5:26using a programming language it might be
139. 5:29created through a dbms utility program
140. 5:32having a dbms between the end user's
141. 5:35application
142. 5:36in the database offers some important
143. 5:38advantages
144. 5:40first the dbms enables the data
145. 5:43in the dbms to be shared among multiple
146. 5:45applications or users
147. 5:47second the dbms integrates the many
148. 5:50different users views
149. 5:52of the data into a single all
150. 5:54encompassing
151. 5:55data repository
152. 6:01a dbms can be used to build many
153. 6:04different types of databases
154. 6:06each database stores a particular
155. 6:08collection of data
156. 6:09and is used for a specific purpose the
157. 6:12number of users determines whether the
158. 6:14database is classified
159. 6:16as a single user or multi-user
160. 6:19a single user database supports only one
161. 6:21user
162. 6:22at a time if user a is using the
163. 6:26database
164. 6:27users b and c must wait until user a is
165. 6:30done
166. 6:31a single user database that runs on a
167. 6:33personal computer
168. 6:34is called a desktop database in contrast
169. 6:38a multi-user database supports multiple
170. 6:41users at the same time when the
171. 6:44multi-user database supports
172. 6:46a relatively small number of users
173. 6:50can be fewer than 50 or specific
174. 6:52department within an
175. 6:54organization it is called a work
176. 6:57group database when the database is used
177. 7:00by the entire organization
178. 7:02and supports many users which is more
179. 7:05than 50.
180. 7:08this is across many departments the
181. 7:10database is known as
182. 7:12an enterprise database
183. 7:18location might also be used to classify
184. 7:21the database for example
185. 7:22a database that supports data located at
186. 7:25a single site
187. 7:26is called a centralized database a
188. 7:29database
189. 7:30that supports data distributed across
190. 7:32several different sites
191. 7:34is called a distributed database both
192. 7:37centralized
193. 7:38and decentralized databases require a
194. 7:41well-defined infrastructure
195. 7:43to implement and operate the database
196. 7:45typically the infrastructure is owned
197. 7:48and maintained by the organization
198. 7:50that creates and operates the database
199. 7:52but in recent years
200. 7:54the use of cloud databases has been
201. 7:56growing in popularity
202. 7:58a cloud database is a database that is
203. 8:01created
204. 8:02and maintained using cloud data services
205. 8:05such as microsoft azure or amazon aws
206. 8:13a popular way of classifying databases
207. 8:16is according to the type of data stored
208. 8:18in them
209. 8:18using this criterion databases are
210. 8:21grouped into two categories
211. 8:23general purpose and discipline specific
212. 8:26general purpose databases contain a wide
213. 8:29variety of data
214. 8:30used in multiple disciplines for example
215. 8:33a census database that contains general
216. 8:36demographic data
217. 8:37discipline specific databases contain
218. 8:40data focus in specific subject areas
219. 8:43like for academic or research purposes
220. 8:46the most popular way of classifying
221. 8:48databases today
222. 8:50is based on how they will be used and on
223. 8:53the time sensitivity of the information
224. 8:56gathered from them for example
225. 8:58transactions such as product or service
226. 9:01sales
227. 9:02payments and supply purchases reflect
228. 9:04critical
229. 9:05day-to-day operations such transactions
230. 9:09must be recorded
231. 9:10accurately and immediately a database
232. 9:13that is designed
233. 9:14primarily to support a company's
234. 9:16day-to-day operations
235. 9:18is classified as an operational database
236. 9:22also known as an online transaction
237. 9:24processing
238. 9:25or oltp database transactional database
239. 9:29or production database
240. 9:35an analytical database focuses primarily
241. 9:38on storing historical data
242. 9:40and business metrics used exclusively
243. 9:43for tactical
244. 9:44or strategic decision-making analytical
245. 9:47databases
246. 9:48allow the end user to perform advanced
247. 9:51analysis of business data using
248. 9:54sophisticated tools
249. 9:56typically analytical databases comprise
250. 9:59two main components a data warehouse
251. 10:03and an online analytical processing
252. 10:05front end
253. 10:07the data warehouse is a specialized
254. 10:09database that stores data
255. 10:11in a format optimized for decision
256. 10:14support
257. 10:15online analytical processing or orlap
258. 10:19is a set of tools that work together to
259. 10:21provide
260. 10:22an advanced data analysis environment
261. 10:25for retrieving
262. 10:26processing and modeling data from the
263. 10:29data warehouse in this recent time
264. 10:33this area of database application has
265. 10:35grown
266. 10:37in importance and usage to the point
267. 10:39that it has evolved
268. 10:40into its own discipline business
269. 10:43intelligence
270. 10:44the term business intelligence describes
271. 10:47a comprehensive approach
272. 10:49to capture and process business data
273. 10:52with the purpose of generating
274. 10:54information
275. 10:55to support business decision making
276. 11:05databases can also be classified to
277. 11:07reflect the degree to which the data is
278. 11:09structured
279. 11:10unstructured data is data that exists in
280. 11:13its original state
281. 11:15in a format that does not lend itself to
282. 11:17the processing that yields
283. 11:19information structured data
284. 11:22is the result of formatting unstructured
285. 11:24data
286. 11:25to facilitate storage use and generation
287. 11:28of information
288. 11:30you apply structure or format based on
289. 11:33the type of processing
290. 11:34that you intend to perform on the data
291. 11:37for example
292. 11:38printed paper invoices can be scanned
293. 11:41and saved
294. 11:42in a graphic format as images for future
295. 11:45retrieval and display
296. 11:47most data which is classified as
297. 11:51semi-structured
298. 11:52have already been processed to some
299. 11:54extent if you look at a typical web page
300. 11:57they also use semi-structured and
301. 12:00unstructured data
302. 12:02unstructured and semi-structured data
303. 12:04storage
304. 12:05and management needs are being addressed
305. 12:08through a new generation of databases
306. 12:11known as
307. 12:12xml extensible markup language
308. 12:16is a special language used to represent
309. 12:18and manipulate data elements
310. 12:20in a text wall format an xml
311. 12:24database supports the storage and
312. 12:26management
313. 12:27of same structured xml data
314. 12:34why database design is important
315. 12:36database design refers to the activities
316. 12:39that focus on the design of the
317. 12:41databases structure
318. 12:42that will be used to store and manage
319. 12:44end-user data
320. 12:46data is one of an organization's most
321. 12:50valuable assets well-designed database
322. 12:54facilitates data management
323. 12:56and generates accurate and valuable
324. 12:58information
325. 13:00poorly designed database can cause
326. 13:02difficult to trace errors that may lead
327. 13:05to poor decision
328. 13:06making
329. 13:10a brief explanation of the evolution of
330. 13:13file system data processing
331. 13:15can be helpful in understanding the data
332. 13:17access limitations
333. 13:19that databases attempt to overcome
334. 13:22to be successful an organization must
335. 13:24develop systems for handling
336. 13:27core business tasks manual file systems
337. 13:30was accomplished
338. 13:31through a system of file folders and
339. 13:33filing cabinets
340. 13:35generating reports from manual file
341. 13:38systems was slow
342. 13:39and cumbersome data processing
343. 13:42specialists was hired
344. 13:44to create a computer-based system that
345. 13:46would track
346. 13:47data and produce required reports
347. 13:50the user's desire for direct hands-on
348. 13:53access to data
349. 13:55help to fuel the adoption of personal
350. 13:58computers for business use
351. 14:00file system redox as a modern end user
352. 14:03productivity tools
353. 14:04includes spreadsheet programs such as
354. 14:07microsoft excel
355. 14:13the description of computer files
356. 14:15requires a specialized vocabulary
357. 14:18table 1.2 will help you to understand
358. 14:21subsequent discussions more easily
359. 14:24the term data said to be real facts
360. 14:27it has little meaning unless it has been
361. 14:29organized in some logical manner
362. 14:32field a character group of characters
363. 14:35that has a specific meaning a field is
364. 14:38used to define and store data
365. 14:41record a logically connected set of one
366. 14:43or more fields
367. 14:45that describes a person place your thing
368. 14:47then file
369. 14:49a collection of related records
370. 14:55in figure 1.9 each file in the system
371. 14:58use its own application program
372. 15:01to store retrieve and modify data also
373. 15:05each file was owned by the individual or
374. 15:07the department that commissioned
375. 15:09its creation the advent of computer
376. 15:12files to store company data was
377. 15:14significant
378. 15:15it not only established a landmark in
379. 15:18the use of computer technologies
380. 15:20but also represented a huge step
381. 15:28the next slide will continue the
382. 15:29discussion of fundamentals of database
383. 15:32regarding the problems with file system
384. 15:34data processing