Dimension of a table

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Description

Display the dimension of the table that a db.table object points to.

Usage

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## S4 method for signature 'db.table'
dim(x)

## S4 method for signature 'db.view'
dim(x)

## S4 method for signature 'db.Rquery'
dim(x)

Arguments

x

A db.obj. Only for db.table object, this function gives the dimension of table that x points to. For db.view and db.Rquery objects, an error message is raised.

Value

A two-integer array, where the first integer is the number of rows and the second integer is the number of columns.

Author(s)

Author: Predictive Analytics Team at Pivotal Inc.

Maintainer: Frank McQuillan, Pivotal Inc. fmcquillan@pivotal.io

See Also

db.obj, db.data.frame, db.table, db.view, db.Rquery are the class hierarchy structure of this package.

Examples

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## Not run: 


## set up the database connection
## Assume that .port is port number and .dbname is the database name
cid <- db.connect(port = .port, dbname = .dbname, verbose = FALSE)

## create a table from the example data.frame "abalone"
delete("abalone", conn.id = cid)
x <- as.db.data.frame(abalone, "abalone", conn.id = cid, verbose = FALSE)
## preview of a table
lk(x, nrows = 10) # extract 10 rows of data

## get names of all columns
dim(x)

dim(x[,1:3])

db.disconnect(cid, verbose = FALSE)

## End(Not run)

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