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Table a and table B, after changing sides, use explain. The result is a little unexpected. Why
2022-02-02 22:48:49 【CSDN Q & A】
Separate use explain analysis ,test1 Tabular Primary key id relation test2 Tabular test_id
test2 Index of tables
Come on, come on , Discuss the duck together
Refer to the answer 1：
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Refer to the answer 2：
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