本文探讨了使用SQL进行数据计数的不同方法及其效率对比。推荐使用`SELECT COUNT(*) FROM tableName;`来处理大规模数据，避免使用`SELECT COUNT(column) FROM tableName;`，因为它效率较低。
---- select count (*) from tableName;
This is the optimal choice when you face Mass Data;
---- select cout(*) from tableName where column = 'value'；
This method is just so-so so-so. Its efficiency is low;
And the bad method is :
---- select count (column) from tableName;
We should try not to contact this method;
This is the optimal choice when you face Mass Data;
---- select cout(*) from tableName where column = 'value'；
This method is just so-so so-so. Its efficiency is low;
And the bad method is :
---- select count (column) from tableName;
We should try not to contact this method;
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