sql {dplyr} | R Documentation |
These functions are critical when writing functions that translate R functions to sql functions. Typically a conversion function should escape all it's inputs and return an sql object.
sql(...) ident(...) is.sql(x) is.ident(x) escape(x, parens = NA, collapse = " ", con = NULL) sql_vector(x, parens = NA, collapse = " ", con = NULL)
... |
Character vectors that will be combined into a single SQL
expression. |
x |
An object to escape. Existing sql vectors will be left as is,
character vectors are escaped with single quotes, numeric vectors have
trailing |
parens, collapse |
Controls behaviour when multiple values are supplied.
Default behaviour: lists are always wrapped in parens and separated by commas, identifiers are separated by commas and never wrapped, atomic vectors are separated by spaces and wrapped in parens if needed. |
# Doubles vs. integers escape(1:5) escape(c(1, 5.4)) # String vs known sql vs. sql identifier escape("X") escape(sql("X")) escape(ident("X")) # Escaping is idempotent escape("X") escape(escape("X")) escape(escape(escape("X")))