MySQL ?? ??? ? ???? ???
MySQL?? ??? ? ???? ??? ????? MAX( ) ? CASE ??? GROUP BY ?? ?? ?????. ?? ??? ??? ????.
SELECT GROUP_BY_COLUMNS, MAX(CASE WHEN condition1 THEN column1 END) AS column1_alias, MAX(CASE WHEN condition2 THEN column2 END) AS column2_alias, ... FROM TABLE GROUP BY GROUP_BY_COLUMNS
??? ??? ? ?? ???? ????. ??? ??? ??? ??; ???? ??? ???? ?? ? ??? ?? ??? ??? ??? ??.
?? ??? ? ?? ??? ?? ????? ?? ??? ??? ? ????.
SELECT a.ID,
a.user_ID,
a.job_id,
MAX(CASE WHEN c.question = 'Is it this?' THEN b.answer END) 'Is it this?',
MAX(CASE WHEN c.question = 'Or this?' THEN b.answer END) 'Or this?',
MAX(CASE WHEN c.question = 'Or that? ' THEN b.answer END) 'Or that? '
FROM Results a
INNER JOIN Answers b
ON a.id = b.fk_result_id
INNER JOIN Question c
ON b.fk_question_id = c.ID
GROUP BY a.ID,
a.user_ID,
a.job_id
? ??? fk_question_id ??? ???? ?? ?? ???? fk_result_id ??? ???? ?? ?? ???? ?? ?? ??????. ?? ?? ??? ID, user_ID, job_id ??? ????? ? ??? ?? MAX() ??? CASE ?? ???? ? ??? ?? ?? ??? ?????.
?? ??? ?? ?? ?? ??? ? ? ?? ?? ?? ??? ??? ???? ?? ???? ???? ?? SQL ??? ??? ? ????.
SET @sql = NULL;
SELECT
GROUP_CONCAT(DISTINCT
CONCAT(
'MAX(CASE WHEN c.question = ''',
question,
''' then b.answer end) AS ',
CONCAT('`',question,'`')
)
) INTO @sql
FROM Question;
SET @sql = CONCAT('SELECT a.ID,
a.user_ID,
a.job_id, ', @sql, '
FROM Results a
INNER JOIN Answers b
ON a.id = b.fk_result_id
INNER JOIN Question c
ON b.fk_question_id = c.ID
GROUP BY a.ID,
a.user_ID,
a.job_id');
PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
?? ??? @sql? ?????. ? ??? ??? ?? ??? ???? ??? ????? ?????.
??? ??? ?? ??? ? ?? ??? ?? ????? ????? ??? ???? ??? ? ????.
? ??? MySQL ??? ? ???? ??? ???? ??? ??????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!
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Undress AI Tool
??? ???? ??
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???? ?? ??? ??? ?? AI ?? ?
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???? ?? ???? ??? AI ?????.
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AI ? ???
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??? ??? AI ?? ?? ??? ???? ?? ???? ??? ?? ????!
?? ??
??? ??
???++7.3.1
???? ?? ?? ?? ???
SublimeText3 ??? ??
??? ??, ???? ?? ????.
???? 13.0.1 ???
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??? ? ?? ??
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? ??? ?? ?? ?????(SublimeText3)
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