Returns the plan optimization strategy of a SQL statement in XML format, as a string.
GRAPHICAL_PLAN( string-expression [, statistics-level [, cursor-type [, update-status ] ] ] )
string-expression The SQL statement, which is commonly a SELECT statement but which may also be an UPDATE or DELETE statement.
statistics-level An integer. Statistics-level can be one of the following values:
|0||Optimizer estimates only (default).|
|2||Detailed statistics including node statistics.|
cursor-type A cursor type, expressed as a string. Possible values are: asensitive, insensitive, sensitive, or keyset-driven. If cursor-type is not specified, asensitive is used by default.
update-status A string parameter accepting one of the following values indicating how the optimizer should treat the given cursor:
|READ-ONLY||The cursor is read-only.|
|READ-WRITE (default)||The cursor can be read or written to.|
|FOR UPDATE||The cursor can be read or written to. This is exactly the same as READ-WRITE.|
SQL/2008 Vendor extension.
The following Interactive SQL example passes a SELECT statement as a string parameter and returns the plan for executing the query. It saves the plan in the file plan.saplan which can be opened and read using Interactive SQL.
SELECT GRAPHICAL_PLAN( 'SELECT * FROM Departments WHERE DepartmentID > 100' ); OUTPUT TO 'plan.saplan' FORMAT TEXT QUOTE '' HEXADECIMAL ASIS;
The following statement returns a string containing the graphical plan for a keyset-driven, updatable cursor over the query
SELECT * FROM Departments WHERE DepartmentID > 100. It also causes the server to annotate the plan with actual execution statistics, in addition to the estimated statistics
that were used by the optimizer.
SELECT GRAPHICAL_PLAN( 'SELECT * FROM Departments WHERE DepartmentID > 100', 2, 'keyset-driven', 'for update' );
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