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| mysql> select benchmark(1000000000,LEFT('coucou',1)='c');
+--------------------------------------------+
| benchmark(1000000000,LEFT('coucou',1)='c') |
+--------------------------------------------+
| 0 |
+--------------------------------------------+
1 row in set (1 min 15.72 sec)
mysql> select benchmark(1000000000,'coucou' like 'c%');
+------------------------------------------+
| benchmark(1000000000,'coucou' like 'c%') |
+------------------------------------------+
| 0 |
+------------------------------------------+
1 row in set (50.69 sec)
mysql> select benchmark(1000000000,'coucou' between 'c' and 'd');
+----------------------------------------------------+
| benchmark(1000000000,'coucou' between 'c' and 'd') |
+----------------------------------------------------+
| 0 |
+----------------------------------------------------+
1 row in set (1 min 27.05 sec)
mysql> select benchmark(1000000000,'coucou' REGEXP '^c.*');
+----------------------------------------------+
| benchmark(1000000000,'coucou' REGEXP '^c.*') |
+----------------------------------------------+
| 0 |
+----------------------------------------------+
1 row in set (5 min 46.77 sec)
mysql> select benchmark(1000000000,LEFT('coucou',1)='c');
+--------------------------------------------+
| benchmark(1000000000,LEFT('coucou',1)='c') |
+--------------------------------------------+
| 0 |
+--------------------------------------------+
1 row in set (1 min 16.28 sec) |
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