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MySQL शो टेबल स्टेटस, ऑटो इंक्रीमेंट सही नहीं है

यह एक विशेषता है .. बग नहीं।

तालिका आँकड़े कैश किए गए हैं। कैशे को अक्षम करने के लिए और हमेशा नवीनतम संस्करण रखने के लिए आपको सर्वर वैरिएबल को बदलना चाहिए जो कैश-क्लियर की अवधि को इंगित करता है 0:

SET PERSIST information_schema_stats_expiry = 0

Mysql 8.x

. में इस संपत्ति का डिफ़ॉल्ट मान 86400 (24 घंटे) में बदल गया है

उदाहरण:

SET PERSIST information_schema_stats_expiry = 86400
-- 86400 is the default value of mysql 8.x  if you have never changed this you don't need to set this


show variables like 'information_schema_stats_expiry';

+---------------------------------+-------+
| Variable_name                   | Value |
+---------------------------------+-------+
| information_schema_stats_expiry | 86400 |
+---------------------------------+-------+

create schema mytest;

create table `test` (
    `id` int(5) not null auto_increment,
    `name` varchar(256),
    PRIMARY KEY(`id`)
);

insert into test values(null,'name1')
insert into test values(null,'name2')
insert into test values(null,'name3')

show table status where name like 'test';
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
| Name | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time         | Update_time         | Check_time | Collation          | Checksum | Create_options | Comment |
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
| test | InnoDB |      10 | Dynamic    |    3 |           5461 |       16384 |               0 |            0 |         0 |              4 | 2018-10-09 15:32:15 | 2018-10-09 15:32:16 | NULL       | utf8mb4_0900_ai_ci |     NULL |                |         |
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
-- The Auto_increment field is correctly set to 4.. but is now cached.

insert into test values(null,'name3');

show table status where name like 'test';
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
| Name | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time         | Update_time         | Check_time | Collation          | Checksum | Create_options | Comment |
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
| test | InnoDB |      10 | Dynamic    |    3 |           5461 |       16384 |               0 |            0 |         0 |              4 | 2018-10-09 15:32:15 | 2018-10-09 15:32:16 | NULL       | utf8mb4_0900_ai_ci |     NULL |                |         |
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
-- The Auto_increment is still 4 (it was cached).

drop schema mytest

अब हम कॉन्फ़िगरेशन बदलते हैं:

SET PERSIST information_schema_stats_expiry = 0

और हम एक ही परीक्षण चलाते हैं:

show variables like 'information_schema_stats_expiry'


+---------------------------------+-------+
| Variable_name                   | Value |
+---------------------------------+-------+
| information_schema_stats_expiry | 0     |
+---------------------------------+-------+

create schema mytest;
create table `test` (
    `id` int(5) not null auto_increment,
    `name` varchar(256),
    PRIMARY KEY(`id`)
);

insert into test values(null,'name1');
insert into test values(null,'name2');
insert into test values(null,'name3');

show table status where name like 'test';

+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
| Name | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time         | Update_time         | Check_time | Collation          | Checksum | Create_options | Comment |
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
| test | InnoDB |      10 | Dynamic    |    3 |           5461 |       16384 |               0 |            0 |         0 |              4 | 2018-10-09 15:32:49 | 2018-10-09 15:32:49 | NULL       | utf8mb4_0900_ai_ci |     NULL |                |         |
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
--  Auto_increment is 4, but the result is not cached!

insert into test values(null,'name3');



show table status where name like 'test';


+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
| Name | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time         | Update_time         | Check_time | Collation          | Checksum | Create_options | Comment |
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
| test | InnoDB |      10 | Dynamic    |    4 |           4096 |       16384 |               0 |            0 |         0 |              5 | 2018-10-09 15:32:49 | 2018-10-09 15:32:49 | NULL       | utf8mb4_0900_ai_ci |     NULL |                |         |
+------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+--------------------+----------+----------------+---------+
-- The  Auto_increment field is now 5 (a correct, not cached value)

drop schema mytest;



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