DBI (version 1.2.2)

dbExistsTable: Does a table exist?

Description

Returns if a table given by name exists in the database.

DBI:::methods_as_rd("dbExistsTable")

Usage

dbExistsTable(conn, name, ...)

Value

dbExistsTable() returns a logical scalar, TRUE if the table or view specified by the name argument exists, FALSE otherwise.

This includes temporary tables if supported by the database.

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"')

...

Other parameters passed on to methods.

Failure modes

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 dbQuoteIdentifier() or if this results in a non-scalar.

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: dbExistsTable() will do the quoting, perhaps by calling dbQuoteIdentifier(conn, x = name)

• If the result of a call to dbQuoteIdentifier(): no more quoting is done

For all tables listed by dbListTables(), dbExistsTable() returns TRUE.

See Also

Other DBIConnection generics: DBIConnection-class, dbAppendTable(), dbAppendTableArrow(), dbCreateTable(), dbCreateTableArrow(), dbDataType(), dbDisconnect(), dbExecute(), dbGetException(), dbGetInfo(), dbGetQuery(), dbGetQueryArrow(), dbIsReadOnly(), dbIsValid(), dbListFields(), dbListObjects(), dbListResults(), dbListTables(), dbQuoteIdentifier(), dbReadTable(), dbReadTableArrow(), dbRemoveTable(), dbSendQuery(), dbSendQueryArrow(), dbSendStatement(), dbUnquoteIdentifier(), dbWriteTable(), dbWriteTableArrow()

Examples

if (FALSE) { # requireNamespace("RSQLite", quietly = TRUE)
con <- dbConnect(RSQLite::SQLite(), ":memory:")

dbExistsTable(con, "iris")
dbWriteTable(con, "iris", iris)
dbExistsTable(con, "iris")

dbDisconnect(con)
}