Updating a cursor
Similar to calling functions, described in Section 4.3, it is also allowed to mix positional and named notation.
Examples (these use the cursor declaration examples above): Once a cursor has been opened, it can be manipulated with the statements described here.
While we won't be looking at the use of multiple cursors within the same stored proc, it is entirely possible to have multiple cursors in the same code block, but each cursor must have a unique name. HANDLER statement specifies a handler that deals with one or more conditions.
If one of these conditions occurs, the specified statement executes.
Be aware that you can't call he cursor does not require us to select the data based on a key; we can just grab all of it.
The option to use a string as opposed to an integer is designed to be used when column aliases and names are used in the SQL query that generated the result set.In positional notation, all arguments are specified in order.In named notation, each argument's name is specified using to separate it from the argument expression.Rather than executing a whole query at once, it is possible to set up a cursor that encapsulates the query, and then read the query result a few rows at a time.
One reason for doing this is to avoid memory overrun when the result contains a large number of rows.
In cases where the value is treated as a string anyway, there is no drawback.