EXPLAIN SELECT * FROM mt_table WHERE id= 1;
EXPLAIN SELECT * FROM mt_table WHERE id="1"
the database has more than 300000 data id as primary keys. Why do both of them have the same execution plan, leaving the index and scanning only one piece of data?
ps: database has inconsistent field types and will not move the index. This is the theoretical support, but now it is contrary to the theory to solve
has been measured, and the conclusion is as follows:
can you try adding double quotation marks?
I think the primary key is an index.
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