oracle为什么每个表只允许一个LONG列? [英] why oracle allows only one LONG column per table?

问题描述

谁能说出为什么oracle在每个表中只允许一个"LONG"数据类型列.

Could anybody tell why oracle allows only one "LONG" datatype column per table.

推荐答案

LONG是与表数据内联存储的，因此Oracle可能会将其限制为每个表一个，因为这会导致性能下降(因为您进行了大量的扫描)块)，而LOB仅针对前几k内联存储，然后进入LOB段进行其余存储.

LONGs were stored inline with the table data, so Oracle probably limited it to one per table because of that (performance hit as you'd be scanning over a lot of blocks) whereas LOBs are stored inline for only the first few k then go into the LOB segment for the rest.

由于LONG已完全折旧，并且要处理的屁股很痛，因此请尽可能远离它们.

As LONGs are totally depreciated and a major pain in the butt to deal with, stay well away from them where possible.

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