Issue a query to the current database connection
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a query string
a character vector of substitution values
list of commands to be
fetch returns the result of a query as a data frame. If
NULL or empty, then an attempt will be made to retrieve
any pending resutls from previous queries. Note that query results are not
cleared until the next query is issued so
fetch will continue to
return results until a new query is issued.
execute is a wrapper around
query. It will raise
an exception if the command does not complete. Exceptions can be caught with
tryCatch. You cannot use a parameterized
query it will
arguments into a single string.
result_dim returns the number of tuples and fields
|PGRES_EMPTY_QUERY||The string sent to the server was empty|
|PGRES_COMMAND_OK||Successful completion of a command returning no data|
|PGRES_TUPLES_OK||Successful completion of a command returning data (such as a SELECT or SHOW)|
|PGRES_COPY_OUT||Copy Out (from server) data transfer started|
|PGRES_COPY_IN||Copy In (to server) data transfer started|
|PGRES_BAD_RESPONSE||The server's response was not understood.|
|PGRES_NONFATAL_ERROR||A nonfatal error (a notice or warning) occurred|
|PGRES_FATAL_ERROR||A fatal error occurred|
|PGRES_COPY_BOTH||Copy In/Out (to and from server) data transfer started. This is currently used only for streaming replication|
query_error returns an error string
fetch returns a data frame or a query status object on failure.
execute the result status string
Timothy H. Keitt
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## Not run: createdb("rpgtesting") connect("rpgtesting") begin() execute("DROP SCHEMA IF EXISTS rpgtesting CASCADE") execute("CREATE SCHEMA rpgtesting") execute("SET search_path TO rpgtesting") execute("DROP TABLE IF EXISTS test") execute("CREATE TABLE test (id integer, field text)") query("INSERT INTO test VALUES ($1, $2)", c(1, "test")) fetch("SELECT * FROM test") result_dim() fetch("SELECT * FROM testing") query_error() rollback() disconnect() dropdb("rpgtesting") ## End(Not run)
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