sqlParseVariables: Parse interpolated variables from SQL.

Description Usage Arguments Examples

Description

If you're implementing a backend that uses non-ANSI quoting or commenting rules, you'll need to implement a method for sqlParseVariables that calls sqlParseVariablesImpl with the appropriate quote and comment specifications.

Usage

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sqlParseVariables(conn, sql, ...)

sqlCommentSpec(start, end, endRequired)

sqlQuoteSpec(start, end, escape = "", doubleEscape = TRUE)

sqlParseVariablesImpl(sql, quotes, comments)

Arguments

sql

SQL to parse (a character string)

start, end

Start and end characters for quotes and comments

endRequired

Is the ending character of a comment required?

escape

What character can be used to escape quoting characters? Defaults to "", i.e. nothing.

doubleEscape

Can quoting characters be escaped by doubling them? Defaults to TRUE.

quotes

A list of QuoteSpec calls defining the quoting specification.

comments

A list of CommentSpec calls defining the commenting specification.

Examples

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# Use [] for quoting and no comments
sqlParseVariablesImpl("[?a]",
  list(sqlQuoteSpec("[", "]", "\\", FALSE)),
  list()
)

# Standard quotes, use # for commenting
sqlParseVariablesImpl("# ?a\n?b",
  list(sqlQuoteSpec("'", "'"), sqlQuoteSpec('"', '"')),
  list(sqlCommentSpec("#", "\n", FALSE))
)

DBI documentation built on May 2, 2018, 5:04 p.m.