the sum of the binaries stored in the mode field of the
table, why do you find the data record of mode=28 using the query condition where mode & 5?
where mode & 5 and where mode & 1 and mode & 4 query results are different, is there a boss to help with the specific analysis?
28=1C=00011100 , 5000000101 , 28 & 5 = 00000100 = 4 , 4 = TRUE , so it was found out. Do 28 & 1 = 0 , 28 & 4 = 4 , 0 & 4 = 0 = FALSE alone, so you can't find out. A simpler approach is where mode & 5 = 5
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