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If the value in the column is repeatable, how do you find out the unique values?
MySQL and SQL
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If the value in the column is repeatable, how do you find out the unique values?
Use DISTINCT in the query, such as SELECT DISTINCT user_firstname FROM users; You can also ask for a number of distinct values by saying SELECT COUNT (DISTINCT user_firstname) FROM users;
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Other Interview Questions
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- MySQL - Troubleshooting Replication
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- MySQL - Optimization Overview
- MySQL - System/Compile Time and Startup Parameter Tuning
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