filehashRDS-class {filehash}

Filehash RDS Class

Description

An implementation of filehash databases using diretories and separate files

Usage

## S4 method for signature 'filehashRDS,character'
dbInsert(db, key, value, safe = TRUE, ...)

## S4 method for signature 'filehashRDS,character'
dbFetch(db, key, ...)

## S4 method for signature 'filehashRDS,character'
dbMultiFetch(db, key, ...)

## S4 method for signature 'filehashRDS,character'
dbExists(db, key, ...)

## S4 method for signature 'filehashRDS'
dbList(db, ...)

## S4 method for signature 'filehashRDS,character'
dbDelete(db, key, ...)

## S4 method for signature 'filehashRDS'
dbUnlink(db, ...)

Arguments

db

a filehashRDS object

key

character, the name of an R object

value

an R object

safe

Should the operation be done safely?

...

arguments passed to other methods

Details

When safe = TRUE in dbInsert, objects are written to a temp file before replacing any existing objects. This way, if the operation is interrupted, the original data are not corrupted.

For dbMultiFetch, key is a character vector of keys.

Methods (by generic)

• dbInsert(db = filehashRDS, key = character): Insert an R object into a filehashRDS database

• dbFetch(db = filehashRDS, key = character): Retrieve a value from a filehashRDS database

• dbMultiFetch(db = filehashRDS, key = character): Retrieve multiple objects from a filehashRDS database

• dbExists(db = filehashRDS, key = character): Determine if a key exists in a filehashRDS database

• dbList(filehashRDS): Return a character vector of all key stored in a database

• dbDelete(db = filehashRDS, key = character): Delete a key and its corresponding object from a filehashRDS database

• dbUnlink(filehashRDS): Delete an entire filehashRDS database

Slots

dir

Directory where files are stored (filehashRDS only)