I used to know how to do this, but I can't seem to remember or find the answer.
I want to return data from a table and then just add an extra column with a set value (which does not need to be saved). So, it is not an UPDATE
issue. Just a SELECT
with that extra column.
Original table:
| id | col1 | col2 |
| 1 | value1 | value2 |
Return something like this:
| id | col1 | col2 || tmpCol |
| 1 | value1 | value2 || 12:48 |
它很简单:
SELECT id, col1, col2, '12:48' AS tempCol
用这个
select id,col1,col2, '12.48' as tempcol
try this. alter table TableName add column columnName date ; note, put the exact table name in the "TableName that i defined" that u want to add the column and put the column name where i defined the "columnName"
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