spec_sql_quote_literal: spec_sql_quote_literal
In DBItest: Testing DBI Backends
spec_sql_quote_literal R Documentation
spec_sql_quote_literal
Description
spec_sql_quote_literal
Value
dbQuoteLiteral() returns an object that can be coerced to character,
of the same length as the input.
For an empty
integer,
numeric,
character,
logical,
date,
time,
or blob vector,
this function returns a length-0 object.
When passing the returned object again to dbQuoteLiteral()
as x
argument, it is returned unchanged.
Passing objects of class SQL should also return them unchanged.
(For backends it may be most convenient to return SQL objects
to achieve this behavior, but this is not required.)
Specification
The returned expression can be used in a SELECT ... query,
and the value of
dbGetQuery(paste0("SELECT ", dbQuoteLiteral(x)))[[1]]
must be equal to x
for any scalar
integer,
numeric,
string,
and logical.
If x is NA, the result must merely satisfy is.na().
The literals "NA" or "NULL" are not treated specially.
NA should be translated to an unquoted SQL NULL,
so that the query SELECT * FROM (SELECT 1) a WHERE ... IS NULL
returns one row.
Failure modes
Passing a list
for the x argument raises an error.
See Also
Other sql specifications:
spec_sql_append_table,
spec_sql_create_table,
spec_sql_exists_table,
spec_sql_list_fields,
spec_sql_list_objects,
spec_sql_list_tables,
spec_sql_quote_identifier,
spec_sql_quote_string,
spec_sql_read_table,
spec_sql_remove_table,
spec_sql_unquote_identifier,
spec_sql_write_table
DBItest documentation built on June 22, 2024, 11:55 a.m.
R Package Documentation
Browse R Packages
We want your feedback!
Note that we can't provide technical support on individual packages. You should contact the package authors for that.
| spec_sql_quote_literal | R Documentation |
spec_sql_quote_literal
Description
spec_sql_quote_literal
Value
dbQuoteLiteral() returns an object that can be coerced to character,
of the same length as the input.
For an empty
integer,
numeric,
character,
logical,
date,
time,
or blob vector,
this function returns a length-0 object.
When passing the returned object again to dbQuoteLiteral()
as x
argument, it is returned unchanged.
Passing objects of class SQL should also return them unchanged.
(For backends it may be most convenient to return SQL objects
to achieve this behavior, but this is not required.)
Specification
The returned expression can be used in a SELECT ... query,
and the value of
dbGetQuery(paste0("SELECT ", dbQuoteLiteral(x)))[[1]]
must be equal to x
for any scalar
integer,
numeric,
string,
and logical.
If x is NA, the result must merely satisfy is.na().
The literals "NA" or "NULL" are not treated specially.
NA should be translated to an unquoted SQL NULL,
so that the query SELECT * FROM (SELECT 1) a WHERE ... IS NULL
returns one row.
Failure modes
Passing a list
for the x argument raises an error.
See Also
Other sql specifications:
spec_sql_append_table,
spec_sql_create_table,
spec_sql_exists_table,
spec_sql_list_fields,
spec_sql_list_objects,
spec_sql_list_tables,
spec_sql_quote_identifier,
spec_sql_quote_string,
spec_sql_read_table,
spec_sql_remove_table,
spec_sql_unquote_identifier,
spec_sql_write_table
R Package Documentation
Browse R Packages
We want your feedback!
Note that we can't provide technical support on individual packages. You should contact the package authors for that.
Embedding an R snippet on your website
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.