SPI_getvalue(tuple, tupdesc, fnumber)
Input tuple to be examined
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Input tuple description
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Attribute number
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Attribute value or NULL if
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| attribute is NULL |
| �֤�°���� NULL �ξ�硣 |
| fnumber is out of range (SPI_result set to SPI_ERROR_NOATTRIBUTE) |
| ���� fnumber ���ϰϳ��ξ�硣 �� SPI_result �� SPI_ERROR_NOATTRIBUTE �����ꤵ��ޤ����� |
| no output function available (SPI_result set to SPI_ERROR_NOOUTFUNC) |
| ���ϴؿ���̵����硣 �� SPI_result �� SPI_ERROR_NOOUTFUNC ������ ����ޤ����� |