A database (sometimes spelled data base) is also called an electronic database , referring to any collection of data, or information, that is specially organized for rapid search and retrieva l by a computer. Databases are structured to facilitate the storage, retrieva l , modification, and deletion of data in conjunction with various data-processing operations .Databases can be stored on magnetic disk or tape, optical disk, or some other secondary storage device.
A database consists of a file or a set of files. The information in these files may be broken down into records, each of which consists of one or more fields. Fields are the basic units of data storage , and each field typically contains information pertaining to one aspect or attribute of the entity described by the database . Using keywords and various sorting commands, users can rapidly search , rearrange, group, and select the fields in many records to retrieve or create reports on particular aggregate of data.


數(shù)據(jù)庫(kù)（database,有時(shí)拼作data base）又稱為電子數(shù)據(jù)庫(kù)，是專門組織起來(lái)的一組數(shù)據(jù)或信息，其目的是為了便于計(jì)算機(jī)快速查詢及檢索。數(shù)據(jù)庫(kù)的結(jié)構(gòu)是專門設(shè)計(jì)的，在各種數(shù)據(jù)處理操作命令的支持下，可以簡(jiǎn)化數(shù)據(jù)的存儲(chǔ)，檢索，修改和刪除。數(shù)據(jù)庫(kù)可以存儲(chǔ)在磁盤，磁帶，光盤或其他輔助存儲(chǔ)設(shè)備上。
數(shù)據(jù)庫(kù)由一個(gè)或一套文件組成，其中的信息可以分解為記錄，每一記錄又包含一個(gè)或多個(gè)字段（或稱為域）。字段是數(shù)據(jù)存取的基本單位。數(shù)據(jù)庫(kù)用于描述實(shí)體，其中的一個(gè)字段通常表示與實(shí)體的某一屬性相關(guān)的信息。通過(guò)關(guān)鍵字以及各種分類（排序）命令，用戶可以對(duì)多條記錄的字段進(jìn)行查詢，重新整理，分組或選擇，以實(shí)體對(duì)某一類數(shù)據(jù)的檢索，也可以生成報(bào)表。