Question

(a) TEAM table. Team number Team Name City Manager 137 Eagles Orlando Smith 275 Cowboys San Jose Jones 294 Statesmen Springfield Edwards 368 Pandas El Paso Adams 422 Sharks Jackson Vega (b) PLAYER table. Player Number Player Name Age Position Team Number 1209 Steve Marks 24 Catcher 294 1254 Roscoe Gomez 19 Pitcher 422 1536 Mark Norton First Baseman 368 1953 Alan Randall Pitcher 137 2753 John Harbor Shortstop 294 | 24 22 27 20 2843 John Yancy Center Fielder 137 3002 Stuart Clark Catcher 422 3274 Lefty Smith Third Baseman 137 3388 Kevin Taylor Shortstop 294 3740 Juan Vidora Catcher 368 a) the value 294 appears as a team number once in the TEAM table and three times in the PLAYER table. Does this constitute data redundancy, explain? b) First, merge the TEAM and PLAYER tables based on the common Team Number field (in a manner similar to Figure 3.8 for the General Hardware database.) Then answer the following questions: is the merged table improved (compared to the two separate tables) in terms of over data redundancy? Explain ii) Is the merged table improved (compared to the two separate tables) in terms of over data integration? Explain. c) Explain why team number 422 appears twice in the player file d) How many files must be accessed to find: i) the age of player 1953, ii) the name of the team of which player number 2288 plays and iii) the number of the team of player number 2288 plays

Answer 1

a) team number 294 appeared three times in PLAYER table does not cause Redundancy because TEAM and PLAYER table related with One to Many Relationship. When there is a relationship One to Many the primary key of One table should be placed in to the many table so it is necessary and does not cause redundancy.

b) i) The merged table does not improve on Data redundancy, because for each team number we have to repeat it player information.

ii) The merged table does not improve on Data Integration, because for each team number we have to repeat it player information so it is difficult to maintain data integrity that we need to update info on more than one record.

c)team number 422 appeared three times in PLAYER table because TEAM and PLAYER table related with One to Many Relationship. When there is a relationship One to Many the primary key of One table should be placed in to the many table so it is necessary.

d) i) One File : PLAYER, both required field are present in this file.

ii)Two Files: TEAM, PLAYER, we need information like Team Name and Player No which is present in separate file so we need both the files.

iii)One File : PLAYER, we need Team Number and Player Number which is present in PLAYER file so we need only one file.