| Type: | Package |
| Title: | Connection wrapper to SQLite databases |
| Version: | 0.1.0 |
| Author: | Wilson Freitas <wilson.freitas@gmail.com> |
| Maintainer: | Wilson Freitas <wilson.freitas@gmail.com> |
| URL: | https://github.com/wilsonfreitas/sqliter/ |
| Description: | sqliter helps users, mainly data munging practioneers, to organize their sql calls in a clean structure. It simplifies the process of extracting and transforming data into useful formats. |
| License: | MIT + file LICENSE |
| Imports: | stringr, functional, DBI, RSQLite |
| Collate: | 'sqliter.R' |
| Packaged: | 2014-01-26 18:21:10 UTC; wilson |
| NeedsCompilation: | no |
| Repository: | CRAN |
| Date/Publication: | 2014-01-26 19:54:31 |
Functions to wrap SQLite calls
Description
sqliter helps users, mainly data munging practioneers, to organize their sql calls in a clean structure. It simplifies the process of extracting and transforming data into useful formats.
execute query into a given database
Description
Once you have a sqliter database properly set you
can execute queries into that database and get your data
transformed. By default this function returns a
data.frame object, but if you transform your data you can
get whatever you need.
Usage
execute(object, ...)
## S3 method for class 'sqliter'
execute(object, database, query,
post_proc = identity, ...)
Arguments
object |
|
database |
the SQLite database filename without extension |
query |
the query string |
post_proc |
a function to transform data, it receives a database and returns whatever you need. |
... |
additional arguments used by prepared queries |
Examples
## Not run:
DBM <- sqliter(path=c("data", "another/project/data"))
ds <- execute(DBM, "dummydatabase", "select count(*) from dummytable")
ds <- execute(DBM, "dummydatabase", "select * from dummytable where
name = :name", name=c("Macunamima", "Borba Gato"))
ds <- execute(DBM, "dummydatabase", "select * from dummytable where
name = :name", name=c("Macunamima", "Borba Gato"),
post_proc=function(ds) {
ds <- transform(ds, birthday=as.Date(birthday))
ds
})
## End(Not run)
returns the paths of the given database
Description
returns the paths of the given database
Usage
find_database(object, database)
## S3 method for class 'sqliter'
find_database(object, database)
Arguments
object |
|
database |
the SQLite database filename without extension |
Examples
## Not run:
DBM <- sqliter(path=c("data", "another/project/data"))
find_database(DBM, "dummydatabase")
# "data/dummydatabase.db"
## End(Not run)
query functions
Description
**query functions** are dynamic functions which connect
to a database, execute queries in it and transform data.
Actually it is a decorator for execute function.
execute has 5 arguments. The first argument is an
instance of the sqliter class and the second is
the database name. The call to a query function is
executed like a method call to the sqliter object
through the $ operator. The function name must
have the following pattern: query_<database name
without extension>. This call returns an execute
function with the first 2 argument already set. The first
parameter is the sqliter object on which the
$ operator have been called and the second
argument is extracted from the query function name, the
name after the preffix query_.
Examples
## Not run:
DBM <- sqliter(path=c("data", "another/project/data"))
DBM$query_dummydatabase("select count(*) from dummytable")
## End(Not run)
Creates the sqliter a kinf of SQLite database manager, but not that far.
Description
sqliter object works pretty much like a database
manager helping users to execute queries and transform
data through a clean interface.
Usage
sqliter(...)
Arguments
... |
arguments such as |
Examples
## Not run: DBM <- sqliter(path=c("data", "another/project/data"))