If you’re a MySQL user trying ClickHouse, one thing which is
likely to surprise – and annoy you – is the handling of Double
Quotes. In MySQL, you can use both double quotes and single
quotes to quote strings, and as an example, these two queries are
equivalent:
mysql> select * from performance_schema.global_variables where variable_name='max_connections';
+-----------------+----------------+
| VARIABLE_NAME | VARIABLE_VALUE |
+-----------------+----------------+
| max_connections | 151 |
+-----------------+----------------+
1 row in set (0.01 sec)
mysql> select * from performance_schema.global_variables where variable_name="max_connections";
+-----------------+----------------+
| VARIABLE_NAME | VARIABLE_VALUE |
+-----------------+----------------+
| max_connections | 151 |
+-----------------+----------------+
1 row in set (0.00 sec)
This means that many of us tend to use single quotes and double
quotes …
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