rownames {DBI}R Documentation

Convert row names back and forth between columns

Description

These functions provide a reasonably automatic way of preserving the row names of data frame during back-and-forth translation to an SQL table. By default, row names will be converted to an explicit column called "row_names", and any query returning a column called "row_names" will have those automatically set as row names. These methods are mostly useful for backend implementers.

Usage

sqlRownamesToColumn(df, row.names = NA)

sqlColumnToRownames(df, row.names = NA)

Arguments

df

A data frame

row.names

Either TRUE, FALSE, NA or a string.

If TRUE, always translate row names to a column called "row_names". If FALSE, never translate row names. If NA, translate rownames only if they're a character vector.

A string is equivalent to TRUE, but allows you to override the default name.

For backward compatibility, NULL is equivalent to FALSE.

Examples

# If have row names
sqlRownamesToColumn(head(mtcars))
sqlRownamesToColumn(head(mtcars), FALSE)
sqlRownamesToColumn(head(mtcars), "ROWNAMES")

# If don't have
sqlRownamesToColumn(head(iris))
sqlRownamesToColumn(head(iris), TRUE)
sqlRownamesToColumn(head(iris), "ROWNAMES")

[Package DBI version 1.1.2 Index]