9.1.3.11 mysql_eof()

my_bool mysql_eof(MYSQL_RES *result)

Description

This function is deprecated. mysql_errno() or mysql_error() may be used instead.

mysql_eof() determines whether the last row of a result set has been read.

If you acquire a result set from a successful call to mysql_store_result(), the client receives the entire set in one operation. In this case, a NULL return from mysql_fetch_row() always means the end of the result set has been reached and it is unnecessary to call mysql_eof(). When used with mysql_store_result(), mysql_eof() will always return true.

On the other hand, if you use mysql_use_result() to initiate a result set retrieval, the rows of the set are obtained from the server one by one as you call mysql_fetch_row() repeatedly. Because an error may occur on the connection during this process, a NULL return value from mysql_fetch_row() does not necessarily mean the end of the result set was reached normally. In this case, you can use mysql_eof() to determine what happened. mysql_eof() returns a non-zero value if the end of the result set was reached and zero if an error occurred.

Historically, mysql_eof() predates the standard MySQL error functions mysql_errno() and mysql_error(). Because those error functions provide the same information, their use is preferred over mysql_eof(), which is now deprecated. (In fact, they provide more information, because mysql_eof() returns only a boolean value whereas the error functions indicate a reason for the error when one occurs.)

Return Values

Zero if no error occurred. Non-zero if the end of the result set has been reached.

Errors

None.

Example

The following example shows how you might use mysql_eof():

mysql_query(&mysql,"SELECT * FROM some_table");
result = mysql_use_result(&mysql);
while((row = mysql_fetch_row(result)))
{
    // do something with data
}
if(!mysql_eof(result))  // mysql_fetch_row() failed due to an error
{
    fprintf(stderr, "Error: %s\n", mysql_error(&mysql));
}

However, you can achieve the same effect with the standard MySQL error functions:

mysql_query(&mysql,"SELECT * FROM some_table");
result = mysql_use_result(&mysql);
while((row = mysql_fetch_row(result)))
{
    // do something with data
}
if(mysql_errno(&mysql))  // mysql_fetch_row() failed due to an error
{
    fprintf(stderr, "Error: %s\n", mysql_error(&mysql));
}

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