如何根据 MySQL 中的当前值更新字段？
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How to update a field based on its current value in MySQL?
提问by blunders
Is it possible to get the current value of a field, use it as a variable in a calculation, then update the field based on the result?
是否可以获取字段的当前值，将其用作计算中的变量，然后根据结果更新该字段？
For example the record with the ID "1" in table1 has a value of "2"
例如，表 1 中 ID 为“1”的记录的值为“2”
SELECT table1
WHERE ID = "1"
SET RESULT to CurrentID
RESULT = CurrentID + 1;
回答by Oded
This will set the resultcolumn to the value of the CurrentIDcolumn (plus 1) of the same row, for any row that has an IDcolumn that equals "1":
对于具有等于“1”的列的任何行，这会将result列设置为CurrentID同一行的列的值（加 1）ID：
UPDATE table1
SET result = CurrentID + 1
WHERE ID = "1"
回答by John K.
You might try
你可以试试
Update table1 set ID = ID+1 where ID = 1
