DBI (version 0.4-1)

sqlParseVariables: Parse interpolated variables from SQL.

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

sqlParseVariables(con, sql, ...)
"sqlParseVariables"(con, sql, ...)
sqlCommentSpec(start, end, endRequired)
sqlQuoteSpec(start, end, escape = "", doubleEscape = TRUE)
sqlParseVariablesImpl(sql, quotes, comments)

Arguments

sql
SQL to parse (a character vector of length 1)
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

Run this code
# 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))
)

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