spec_result_roundtrip

spec_result_roundtrip

Specification

The column types of the returned data frame depend on the data returned:

• integer (or coercible to an integer) for integer values between -2^31 and 2^31 - 1, with NA for SQL NULL values

• numeric for numbers with a fractional component, with NA for SQL NULL values

• logical for Boolean values (some backends may return an integer); with NA for SQL NULL values

• character for text, with NA for SQL NULL values

• lists of raw for blobs with NULL entries for SQL NULL values

• coercible using as.Date() for dates, with NA for SQL NULL values (also applies to the return value of the SQL function current_date)

• coercible using hms::as_hms() for times, with NA for SQL NULL values (also applies to the return value of the SQL function current_time)

• coercible using as.POSIXct() for timestamps, with NA for SQL NULL values (also applies to the return value of the SQL function current_timestamp)

If dates and timestamps are supported by the backend, the following R types are used:

• lubridate::Date for dates (also applies to the return value of the SQL function current_date)

• lubridate::POSIXct for timestamps (also applies to the return value of the SQL function current_timestamp)

R has no built-in type with lossless support for the full range of 64-bit or larger integers. If 64-bit integers are returned from a query, the following rules apply:

• Values are returned in a container with support for the full range of valid 64-bit values (such as the integer64 class of the bit64 package)

• Coercion to numeric always returns a number that is as close as possible to the true value

• Loss of precision when converting to numeric gives a warning

• Conversion to character always returns a lossless decimal representation of the data

See also

Other result specifications: spec_result_clear_result, spec_result_create_table_with_data_type, spec_result_execute, spec_result_fetch, spec_result_get_query, spec_result_send_query, spec_result_send_statement