ecpg �λȤ���

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15) The preprocessor is called ecpg. After installation it resides in the Postgres bin/ directory.

�ץ�ץ����å��� ecpg �Ȥ���̾���Ǥ��� ���󥹥ȡ��뤹��� Postgres �� bin/ �ǥ��쥯�ȥ���֤���ޤ���

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17) The ecpg library is called libecpg.a or libecpg.so. Additionally, the library uses the libpq library for communication to the Postgres server so you will have to link your program with -lecpg -lpq.

ecpg �Υ饤�֥��� libecpg.a ���뤤�� libecpg.so �Ȥ���̾���Ǥ��� �ä��Ƥ��Υ饤�֥��� Postgres �����ФȤ��̿��� libpq �饤�֥���Ȥ��Τǡ� �ץ������Υ�󥯤� -lecpg -lpq ����ꤷ�ʤ���Фʤ�ޤ���

18) The library has some methods that are "hidden" but that could prove very useful sometime.

�饤�֥��Ϥ����Ĥ�����̩�Ρץ᥽�åɤ���äƤ��ޤ����� ���줬���Ȥ���������Ω�Ĥ��Ȥ��狼��Ϥ��Ǥ���

• 19) ECPGdebug(int on, FILE *stream) turns on debug logging if called with the first argument non-zero. Debug logging is done on stream. Most SQL statement logs its arguments and result.

  ECPGdebug(int on, FILE *stream) ���������� 0 �ʳ��ˤ��ƸƤӽФ��ȥǥХå��ѥ����ε�Ͽ�򳫻Ϥ��ޤ��� ���ΥǥХå������� stream ���Ф��ƽ��Ϥ���ޤ��� SQL ʸ�ΤۤȤ�ɤϥ����ˤ��ΰ����ȷ�̤�Ĥ��ޤ���

  20) The most important one (ECPGdo) that is called on almost all SQL statements logs both its expanded string, i.e. the string with all the input variables inserted, and the result from the Postgres server. This can be very useful when searching for errors in your SQL statements.

  �ۤܤ��٤Ƥ� SQL ʸ�ǸƤӽФ����Ǥ���פʥ᥽�å� ECPGdo �ϡ��ܺ٤�ʸ���� ���ʤ�������ѿ����٤Ƥ��������줿��Τȡ�Postgres �����Ф���η�̤�ξ��������˼��ޤ��� ����� SQL ʸ�δְ㤤��õ���Ф��ݤ��������Ω���ޤ���

• ECPGstatus() 21) This method returns TRUE if we are connected to a database and FALSE if not. ���Υ᥽�åɤϥǡ����١�������³����Ƥ������ TRUE �� �����Ǥʤ���� FALSE ���֤��ޤ���

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23) To be able to detect errors from the Postgres server you include a line like

exec sql include sqlca;

Postgres ����Υ��顼�򸡽ФǤ���褦�ˤ���ˤϡ�

exec sql include sqlca;

struct sqlca
{
 char sqlcaid[8];
 long sqlabc;
 long sqlcode;
 struct
 {
  int sqlerrml;
  char sqlerrmc[70];
 } sqlerrm;
 char sqlerrp[8];
 long sqlerrd[6];

24)
 /* 0: empty                                         */
 /* 1: empty                                         */
 /* 2: number of rows processed in an INSERT, UPDATE */
 /*    or DELETE statement                           */
 /* 3: empty                                         */
 /* 4: empty                                         */
 /* 5: empty                                         */
 /* 0: ��                                             */
 /* 1: ��                                             */
 /* 2: INSERT, UPDATE, DELETE ʸ�ǽ������줿�Կ�      */
 /* 3: ��                                             */
 /* 4: ��                                             */
 /* 5: ��                                             */
 char sqlwarn[8];

25)
 /* 0: set to 'W' if at least one other is 'W'       */
 /* 1: if 'W' at least one character string	     */
 /*    value was truncated when it was               */
 /*    stored into a host variable.                  */
 /* 2: empty                                         */
 /* 3: empty                                         */
 /* 4: empty                                         */
 /* 5: empty                                         */
 /* 6: empty                                         */
 /* 7: empty                                         */
 /* 0: ¾�����Ǥ� 'W' �Ǥ���� 'W' �����åȤ���ޤ�   */
 /* 1: 'W' �Ǥ���С��ۥ����ѿ���ʸ���������������� */
 /*    ���ʤ��Ȥ�ҤȤĤ��ͤ�;ʬ���ڤ���Ȥ���Ƥ��� */
 /*    ��                                             */
 /* 2: ��                                             */
 /* 3: ��                                             */
 /* 4: ��                                             */
 /* 5: ��                                             */
 /* 6: ��                                             */
 /* 7: ��                                             */
 char sqlext[8];
} sqlca;

26) If an error occured in the last SQL statement then sqlca.sqlcode will be non-zero. If sqlca.sqlcode is less that 0 then this is some kind of serious error, like the database definition does not match the query given. If it is bigger than 0 then this is a normal error like the table did not contain the requested row. �� if sqlca.sqlcode is less that 0 then �� ..less than 0 then..

ľ���� SQL ʸ�ǥ��顼��ȯ������� sqlca.sqlcode �� 0 �ʳ����ͤˤʤ�ޤ��� �⤷ sqlca.sqlcode �� 0 ��꾮�����ͤǤ���С� �ǡ����١����������Ϳ����줿�䤤��碌�ȹ��פ��ʤ��Ȥ��ä����餫�ο���ʥ��顼�Ǥ��� 0 �����礭���ͤǤ���С� �ơ��֥뤬�׵ᤷ���Ԥ�ޤ�Ǥ��ʤ��ʤɤ����̤Υ��顼�Ǥ���

27) sqlca.sqlerrm.sqlerrmc will contain a string that describes the error. The string ends with the line number in the source file.

sqlca.sqlerrm.sqlerrmc �ˤϥ��顼����������ʸ���󤬴ޤޤ�ޤ��� ʸ����ϥ������ե�������γ������ֹ�ǽ����ޤ���

28) List of errors that can occur:

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