SQL> select 1 from dual where 'john_abc' like 'john/____' escape '/'; 1
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1已用时间: 00: 00: 00.00
SQL> select 1 from dual where 'john_ab' like 'john/____' escape '/';未选定行已用时间: 00: 00: 00.00
SQL>
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1已用时间: 00: 00: 00.00
SQL> select 1 from dual where 'john_ab' like 'john/____' escape '/';未选定行已用时间: 00: 00: 00.00
SQL>
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1有必要用"/"吗?