data structures using search to search record having the key value kiuse (kito compute the address of the bucket where the record is stored the bucket may contain one or several recordsso check for every record in the bucket (by comparing ki with the key of every recordto finally retrieve the desired record with the given key value deletion to delete record with key value kiuse (kito compute the address of the bucket where the record is stored the bucket may contain one or several records so check for every record in the bucket (by comparing ki with the key of every recordthen delete the record as we delete node from linear linked list we have already studied how to delete record from chained hash table in note that in hashed file organizationthe secondary indices need to be organized using hashing points to remember file is block of useful information which is available to computer program and is usually stored on persistent storage medium every file contains data this data can be organized in hierarchy to present systematic organization the data hierarchy includes data items such as fieldsrecordsfilesand database data field is an elementary unit that stores single fact record is collection of related data fields which is seen as single unit from the application point of view file is collection of related records directory is collection of related files database is defined as collection of data organized in fashion that facilitates updatingretrievingand managing the data there are two types of computer files--text files and binary files text file is structured as sequence of lines of alphabetnumbersspecial charactersetc howeverthe data in text file is stored using its corresponding ascii code whereas in binary filesthe data is stored in binary formi in the format it is stored in the memory each file has list of attributes associated with it which can have one of two states--on or off these attributes areread-onlyhiddensystemvolume labelarchiveand directory file marked as read-only cannot be deleted or modified hidden file is not displayed in the directory listing system file is used by the system and should not be altered or removed from the disk the archive bit is useful for communication between programs that modify files and programs that are used for backing up files file that has the directory bit turned on is actually sub-directory containing one or more files file organization means the logical arrangement of records in the file files can be organized as sequentialrelativeor index sequential sequentially organized file stores records in the order in which they were entered in relative file organizationrecords in file are ordered by their relative key relative files can be used for both random access as well as sequential access of data in an indexed sequential fileevery record is uniquely identified by key field we maintain table known as the index table that stores record number and the address of the record in the file there are several indexing techniquesand each technique works well for particular application in dense indexindex table stores the address of every record in the file howeverin sparse indexindex table stores address of only some of the records in the file cylinder surface indexing is very simple technique which is used only for the primary key index of sequentially ordered file in multi-level indexingwe can create an index to the index itself the original index is called the firstlevel index and the index to the index is called the second-level index