The default dbCreateTable()
method calls sqlCreateTable()
and
dbExecute()
.
Use dbCreateTableArrow()
to create a table from an Arrow schema.
Arguments
- conn
A DBIConnection object, as returned by
dbConnect()
.- name
The table name, passed on to
dbQuoteIdentifier()
. Options are:a character string with the unquoted DBMS table name, e.g.
"table_name"
,a call to
Id()
with components to the fully qualified table name, e.g.Id(schema = "my_schema", table = "table_name")
a call to
SQL()
with the quoted and fully qualified table name given verbatim, e.g.SQL('"my_schema"."table_name"')
- fields
Either a character vector or a data frame.
A named character vector: Names are column names, values are types. Names are escaped with
dbQuoteIdentifier()
. Field types are unescaped.A data frame: field types are generated using
dbDataType()
.- ...
Other parameters passed on to methods.
- row.names
Must be
NULL
.- temporary
If
TRUE
, will generate a temporary table.
Details
Backends compliant to ANSI SQL 99 don't need to override it.
Backends with a different SQL syntax can override sqlCreateTable()
,
backends with entirely different ways to create tables need to
override this method.
The row.names
argument is not supported by this method.
Process the values with sqlRownamesToColumn()
before calling this method.
The argument order is different from the sqlCreateTable()
method, the
latter will be adapted in a later release of DBI.
Failure modes
If the table exists, an error is raised; the remote table remains unchanged.
An error is raised when calling this method for a closed
or invalid connection.
An error is also raised
if name
cannot be processed with DBI::dbQuoteIdentifier()
or
if this results in a non-scalar.
Invalid values for the row.names
and temporary
arguments
(non-scalars,
unsupported data types,
NA
,
incompatible values,
duplicate names)
also raise an error.
Additional arguments
The following arguments are not part of the dbCreateTable()
generic
(to improve compatibility across backends)
but are part of the DBI specification:
temporary
(default:FALSE
)
They must be provided as named arguments. See the "Specification" and "Value" sections for details on their usage.
Specification
The name
argument is processed as follows,
to support databases that allow non-syntactic names for their objects:
If an unquoted table name as string:
dbCreateTable()
will do the quoting, perhaps by callingdbQuoteIdentifier(conn, x = name)
If the result of a call to
DBI::dbQuoteIdentifier()
: no more quoting is done
The value
argument can be:
a data frame,
a named list of SQL types
If the temporary
argument is TRUE
, the table is not available in a
second connection and is gone after reconnecting.
Not all backends support this argument.
A regular, non-temporary table is visible in a second connection,
in a pre-existing connection,
and after reconnecting to the database.
SQL keywords can be used freely in table names, column names, and data. Quotes, commas, and spaces can also be used for table names and column names, if the database supports non-syntactic identifiers.
The row.names
argument must be missing
or NULL
, the default value.
All other values for the row.names
argument
(in particular TRUE
,
NA
,
and a string)
raise an error.
See also
Other DBIConnection generics:
DBIConnection-class
,
dbAppendTable()
,
dbAppendTableArrow()
,
dbCreateTableArrow()
,
dbDataType()
,
dbDisconnect()
,
dbExecute()
,
dbExistsTable()
,
dbGetException()
,
dbGetInfo()
,
dbGetQuery()
,
dbGetQueryArrow()
,
dbIsReadOnly()
,
dbIsValid()
,
dbListFields()
,
dbListObjects()
,
dbListResults()
,
dbListTables()
,
dbQuoteIdentifier()
,
dbReadTable()
,
dbReadTableArrow()
,
dbRemoveTable()
,
dbSendQuery()
,
dbSendQueryArrow()
,
dbSendStatement()
,
dbUnquoteIdentifier()
,
dbWriteTable()
,
dbWriteTableArrow()
Examples
con <- dbConnect(RSQLite::SQLite(), ":memory:")
dbCreateTable(con, "iris", iris)
dbReadTable(con, "iris")
#> [1] Sepal.Length Sepal.Width Petal.Length Petal.Width Species
#> <0 rows> (or 0-length row.names)
dbDisconnect(con)