Description

The dbSendQuery() method only submits and synchronously executes the SQL query to the database engine. It does not extract any records — for that you need to use the dbFetch() method, and then you must call dbClearResult() when you finish fetching the records you need. For interactive use, you should almost always prefer dbGetQuery().

Usage

Arguments

Details

This method is for SELECT queries only. Some backends may support data manipulation queries through this method for compatibility reasons. However, callers are strongly encouraged to use dbSendStatement() for data manipulation statements.

The query is submitted to the database server and the DBMS executes it, possibly generating vast amounts of data. Where these data live is driver-specific: some drivers may choose to leave the output on the server and transfer them piecemeal to R, others may transfer all the data to the client – but not necessarily to the memory that R manages. See individual drivers' dbSendQuery() documentation for details.

Value

dbSendQuery() returns an S4 object that inherits from DBIResult. The result set can be used with dbFetch() to extract records. Once you have finished using a result, make sure to clear it with dbClearResult(). An error is raised when issuing a query over a closed or invalid connection, or if the query is not a non-NA string. An error is also raised if the syntax of the query is invalid and all query parameters are given (by passing the params argument) or the immediate argument is set to TRUE.

See Also

For updates: dbSendStatement() and dbExecute().

Other DBIConnection generics: DBIConnection-class, dbAppendTable(), dbCreateTable(), dbDataType(), dbDisconnect(), dbExecute(), dbExistsTable(), dbGetException(), dbGetInfo(), dbGetQuery(), dbIsReadOnly(), dbIsValid(), dbListFields(), dbListObjects(), dbListResults(), dbListTables(), dbReadTable(), dbRemoveTable(), dbSendStatement(), dbWriteTable()