固定成本短期内不随作业量而变化的成本。(又称“不变成本”或“恒定成本”。)
Fixed cost a cost that does not vary with the volume of activity in the short term. (Also called Non-variable cost or Constant cost.)
在一次UPDATE操作,通常保留原样不变字段的值,所以一个UPDATE不得因其不在一直线上的行值TOAST如果没有超行值改变成本。
During an UPDATE operation, values of unchanged fields are normally preserved as-is; so an UPDATE of a row with out-of-line values incurs no TOAST costs if none of the out-of-line values change.
在一次UPDATE操作,通常保留原样不变字段的值,所以一个UPDATE不得因其不在一直线上的行值TOAST如果没有超行值改变成本。
During an UPDATE operation, values of unchanged fields are normally preserved as-is; so an UPDATE of a row with out-of-line values incurs no TOAST costs if none of the out-of-line values change.
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