《IT职业英语》课件7-1-reading

2023/12/12IT职业英语0ContentsDatabase1DBMS23HierarchyofDataOrganization4Databaseoperations2023/12/12IT职业英语1Vocabulary1.database n.数据库2.access vt.存取3.retrieval n.检索4.DBMS（databasemanagementsystem）

n.数据库管理系统5.delete vt.&vi.删除6.sort vt.&vi.分类7.retrieve vt.恢复8.forms n.窗体9.bit n.字10.byte n.字节11.character n.符号，字12.field n.字段13.record n.记录14.update vt.更新2023/12/12IT职业英语2DatabaseAdatabase

isacollectionofdataorganizedinamannerthatallowsaccess,retrieval,anduseofthatdata.2023/12/12IT职业英语3DBMSDatabasesoftware,oftencalledadatabasemanagementsystem(DBMS),allowsuserstocreateacomputerizeddatabase;add,change,anddeletethedata;sort

andretrievethedata;andcreateformsandreportsfromthedata.2023/12/12IT职业英语4HierarchyofData

Organization0,111000001=AAlvinAdamsAlvinAdams,820TiogaAve.NYC,etcAlvinAdams,etc;MaryBirch,etc;…

Employeemaster;Inventorymaster;Customermaster;Suppliermaster.Etc.BitscharactersFieldsRecordsFilesDatabases2023/12/12IT职业英语5HierarchyofData

OrganizationBit:

thesmallestunitofdataacomputercanprocess.Byte:

eightbitsgroupedtogetherinaunitformabyte.

Character:

eachbyterepresentsasinglecharacter,whichcanbeanumber,letter,punctuationmark,orothersymbol.Field:

acombinationofoneormorerelatedcharactersorbytesandisthesmallestunitofdataauseraccesses.Record:agroupof

relatedfields.Datafile:acollectionofrelatedrecordsstoredonastoragemediumsuchasaharddisk,CD,orDVD.2023/12/12IT职业英语6DatabaseoperationsFilescaneasilybeupdated:changefieldsadd

newrecordsdeleteoldones2023/12/12IT职业英语7Exercise1Trueorfalse1. ()Dataaretherawfactsfromwhichinformationisderived.2. ()Intermsofdatastorage,acharacterisusuallythesameasabyte.3. ()Filearesorted,merged,andprocessedbykeyfield.4. ()Arecordisacollectionoffilesthatareinsomewaylogicallyrelatedtooneano