| dbGetRowCount {DBI} | R Documentation |
The number of rows fetched so far
Description
Returns the total number of rows actually fetched with calls to dbFetch()
for this result set.
Usage
dbGetRowCount(res, ...)
Arguments
res |
An object inheriting from DBIResult. |
... |
Other arguments passed on to methods. |
Value
dbGetRowCount() returns a scalar number (integer or numeric),
the number of rows fetched so far.
After calling dbSendQuery(),
the row count is initially zero.
After a call to dbFetch() without limit,
the row count matches the total number of rows returned.
Fetching a limited number of rows
increases the number of rows by the number of rows returned,
even if fetching past the end of the result set.
For queries with an empty result set,
zero is returned
even after fetching.
For data manipulation statements issued with
dbSendStatement(),
zero is returned before
and after calling dbFetch().
Failure modes
Attempting to get the row count for a result set cleared with
dbClearResult() gives an error.
See Also
Other DBIResult generics:
DBIResult-class,
dbBind(),
dbClearResult(),
dbColumnInfo(),
dbFetch(),
dbGetInfo(),
dbGetRowsAffected(),
dbGetStatement(),
dbHasCompleted(),
dbIsReadOnly(),
dbIsValid(),
dbQuoteLiteral(),
dbQuoteString()
Examples
con <- dbConnect(RSQLite::SQLite(), ":memory:")
dbWriteTable(con, "mtcars", mtcars)
rs <- dbSendQuery(con, "SELECT * FROM mtcars")
dbGetRowCount(rs)
ret1 <- dbFetch(rs, 10)
dbGetRowCount(rs)
ret2 <- dbFetch(rs)
dbGetRowCount(rs)
nrow(ret1) + nrow(ret2)
dbClearResult(rs)
dbDisconnect(con)