我有一个MySQL表，布局如下。
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| ID | TITLE | VALUE | PART NO |
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| 1 | width (mm) | 12 | 234 |
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| 2 | colour | red | 234 |
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| 3 | colour | blue | 235 |
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| 4 | width (mm) | 2 | 234 |
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| 5 | Part No. | 235 | 235 |
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| 6 | Part No. | 234 | 234 |
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我想让这个表看起来像这样。
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| id | Width (mm) | colour | Part No. |
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| 1 | 12 | red | 234 |
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| 2 | 2 | blue | 235 |
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我找到了另一个答案，但后来失去了链接 -- -- 这个答案没有解决我的问题，因为它只对数字有效。
我需要SQL代码来说明标题中的（和值中的单词（不只是添加数字）。
我使用我找到的答案创建了下面的SQL，并失去了 - 它的工作原理有点，但我缺少大量的数据，它返回的 "制造商 "列和第一个 "替代Partnumber "列，但没有其他。这让我很困惑--表中有重量和高度100%，而这2个字段在查询中并不相近）。
SQL代码
SELECT
part_number,
part_number AS pn,
if( title = 'Alternative Partnumber', (SELECT table_name.value FROM `table_name` WHERE table_name.part_number = pn AND table_name.title = 'Alternative Partnumber'), '' ) AS `Alternative Partnumber`,
if( title = 'Amp', (SELECT table_name.value FROM `table_name` WHERE table_name.part_number = pn AND table_name.title = 'Amp'), '' ) AS `Amp`,
if( title = 'Amp Rating (Constant Torque)', (SELECT table_name.value FROM `table_name` WHERE table_name.part_number = pn AND table_name.title = "Amp Rating (Constant Torque)"), '' ) AS `Amp Rating (Constant Torque)`,
if( title = 'Analogue Inputs', (SELECT table_name.value FROM `table_name` WHERE table_name.part_number = pn AND table_name.title = "Analogue Inputs"), '' ) AS "Analogue Inputs",
if( title = 'Analogue output', (SELECT table_name.value FROM `table_name` WHERE table_name.part_number = pn AND table_name.title = "Analogue output"), '' ) AS "Analogue output",
if( title = 'Manufacturer', (SELECT table_name.value FROM `table_name` WHERE table_name.part_number = pn AND table_name.title = 'Manufacturer'), '' ) AS `Manufacturer`,
if( title = 'Weight', (SELECT table_name.value FROM `table_name` WHERE table_name.part_number = pn AND table_name.title = 'Weight'), '' ) AS `Weight`,
if( title = 'Width', (SELECT table_name.value FROM `table_name` WHERE table_name.part_number = pn AND table_name.title = 'Width'), '' ) AS `Width`,
if( title = 'Width (mm)', (SELECT table_name.value FROM `table_name` WHERE table_name.part_number = pn AND table_name.title = 'Width (mm)'), '' ) AS `Width (mm)`
FROM
table_name
GROUP BY
part_number;
我需要另一个SQL来做Group By吗？我想这是它丢失数据的地方。
谢谢你，Ryan