检查SQLServer上的XML变量中是否存在XML节点

DECLARE @xml XML = '<root><node1>value1</node1><node2>value2</node2></root>';

IF @xml.exist('/root/node1') = 1
    PRINT 'XML节点存在';
ELSE
    PRINT 'XML节点不存在';

DECLARE @xml XML = '<root><node1>value1</node1><node2>value2</node2></root>';

IF EXISTS (SELECT 1 FROM @xml.nodes('/root/node1') AS T(C))
    PRINT 'XML节点存在';
ELSE
    PRINT 'XML节点不存在';

DECLARE @idoc INT;
DECLARE @xml XML = '<root><node1>value1</node1><node2>value2</node2></root>';

EXEC sp_xml_preparedocument @idoc OUTPUT, @xml;

IF EXISTS (SELECT 1 FROM OPENXML(@idoc, '/root/node1', 2))
    PRINT 'XML节点存在';
ELSE
    PRINT 'XML节点不存在';

EXEC sp_xml_removedocument @idoc;