feat(query): Support access Mysql data from dictionaries via the `dict_get` function.

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Summary

This pull request introduces support for accessing Mysql data from dictionaries using the dict_getfunction.Other source like PostgreSQL will be introduced in the future PRs.Besides, this pull request can only support bool,string,int and float, other types will be supported later.

Dictionary Creation with Mysql Source:

CREATE OR REPLACE DICTIONARY dd3(id int, name string, age int, address string, salary float, b bool) PRIMARY KEY id SOURCE(mysql(host='localhost' port='3306' username='root' password='123456' db='test' table='user3'));

Options are used to provide the Mysql connection URL, host, port, username, password, db and table are all required options to identify specific table.

Connect to Mysql, create a table and insert some records.

mysql -uroot -P3306 -p123456

CREATE TABLE `user3`(`id` int(11), `name` varchar(100), `age` int(11), `address` varchar(100), `salary` float, `b` bool);
INSERT INTO `user3` VALUES(1, 'andy', 10, 'beijing', '1234.56', true);

Data Access with dict_get Function:

MySQL [(none)]> select dict_get(dd3, 'name', 1);
+----------------------------------+
| dict_get(default.dd3, 'name', 1) |
+----------------------------------+
| andy                             |
+----------------------------------+
1 row in set (0.112 sec)

MySQL [(none)]> select dict_get(dd3, 'age', 1);
+---------------------------------+
| dict_get(default.dd3, 'age', 1) |
+---------------------------------+
|                              10 |
+---------------------------------+
1 row in set (0.109 sec)

MySQL [(none)]> select dict_get(dd3, 'salary', 1);
+------------------------------------+
| dict_get(default.dd3, 'salary', 1) |
+------------------------------------+
|                            1234.56 |
+------------------------------------+
1 row in set (0.106 sec)

MySQL [(none)]> select dict_get(dd3, 'b', 1);
+-------------------------------+
| dict_get(default.dd3, 'b', 1) |
+-------------------------------+
|                             1 |
+-------------------------------+
1 row in set (0.077 sec)

The result corresponds to the value stored in Mysql associated with the value of primary key.

If the key is not exists in the Mysql, the result will be NULL:

MySQL [(none)]> select dict_get(dd3, 'b', 5);
+-------------------------------+
| dict_get(default.dd3, 'b', 5) |
+-------------------------------+
|                          NULL |
+-------------------------------+
1 row in set (0.083 sec)

part of https://github.com/datafuselabs/databend/issues/15901

Tests

[x] Unit Test
[ ] Logic Test
[ ] Benchmark Test
[ ] No Test - Explain why

Type of change

[ ] Bug Fix (non-breaking change which fixes an issue)
[x] New Feature (non-breaking change which adds functionality)
[ ] Breaking Change (fix or feature that could cause existing functionality not to work as expected)
[ ] Documentation Update
[ ] Refactoring
[ ] Performance Improvement
[ ] Other (please describe):

This change is

databendlabs / databend