Comprehensive summary of MYSQL tables

1. Create a table

1.1. Basic syntax for creating a table

1.1.1. Create a simple table
1.1.2. View the creation table definition

2. Delete table

3. Modify the table

3.1、Modify table type command

3.2. Field rename command

3.3. Add table field command

3.4. Delete table column field command

3.5. Table rename command

4. DML statements

4.1. Insert record command

4.2. View the insert data command

4.2.1、Query all
4.2.2. Query unique record command keywords
4.2.3. Multiple-condition query keywords
4.2.4, Sorting query naming
4.2.5. Display part, not all, of the instructions
4.2.6. Statistics, Aggregation Instructions
4.2.7. Table Join
4.2.8. Subqueries, related keywords
4.2.9. Recording Joint Instructions

4.3. Update record command

4.4. Delete record naming

4.5. Initialization table

5. DCL Statements

5.1 Create a database user

1. Create a table

1.1. Basic syntax for creating a table

CREATE TABLE tablename (column_name_1 column_type_1 constraints,
column_name_2 column_type_2 constraints , …)

column_name is the name of the column
column_type is the data type of the column
contraints is the constraint condition of this column

1.1.1. Create a simple table

mysql> create table orders (ordername varchar(10),createtime date,ordermoney decimal(10,2),ordernumber int(2));
Query OK, 0 rows affected (0.23 sec)

1.1.2. View the creation table definition

Structural definition:

mysql> desc orders;
+-------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------+------+-----+---------+-------+
| ordername | varchar(10) | YES | | NULL | |
| createtime | date | YES | | NULL | |
| ordermoney | decimal(10,2) | YES | | NULL | |
| ordernumber | int(2) | YES | | NULL | |
+-------------+---------------+------+-----+---------+-------+
4 rows in set (0.00 sec)

Table detailed definition:

View the detailed table definition:

mysql> show create table orders \G;
*************************** 1. row ***************************
       Table: orders
Create Table: CREATE TABLE `orders` (
  `ordername` varchar(10) DEFAULT NULL,
  `createtime` date DEFAULT NULL,
  `ordermoney` decimal(10,2) DEFAULT NULL,
  `ordernumber` int(2) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00 sec)

ERROR:
No query specified

From this we can see that ENGINE (storage engine) of the table is InnoDB

CHARSET is Latin1

The " \G " option allows records to be arranged vertically according to fields, making it easier to display records with longer content.

2. Delete table

Order:

DROP TABLE tablename

Delete orders:

mysql> drop table orders
    -> ;
Query OK, 0 rows affected (0.14 sec)

3. Modify the table

3.1、Modify table type command

ALTER TABLE tablename MODIFY [COLUMN] column_definition [FIRST | AFTER col_name]

Example: Modify the name field definition of the orders table, changing varchar(10) to varchar(20) :

mysql> alter table orders modify ordername varchar(20);
Query OK, 0 rows affected (0.11 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> desc orders;
+-------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------+------+-----+---------+-------+
| ordername | varchar(20) | YES | | NULL | |
| createtime | date | YES | | NULL | |
| ordermoney | decimal(10,2) | YES | | NULL | |
| ordernumber | int(2) | YES | | NULL | |
+-------------+---------------+------+-----+---------+-------+
4 rows in set (0.00 sec)

3.2. Field rename command

ALTER TABLE tablename CHANGE [COLUMN] old_col_name column_definition
[FIRST|AFTER col_name]

Example: Change ordernumber to ordernumbers in the orders table

mysql> alter table orders change column ordernumber ordernumbers int(4);
Query OK, 0 rows affected (0.06 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> desc orders;
+--------------+---------------+-----+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------+---------------+-----+-----+---------+-------+
| ordername | varchar(20) | YES | | NULL | |
| createtime | date | YES | | NULL | |
| ordermoney | decimal(10,2) | YES | | NULL | |
| ordernumbers | int(4) | YES | | NULL | |
+--------------+---------------+-----+-----+---------+-------+
4 rows in set (0.00 sec)

Special note: Both change and modify can modify the definition of a table. The difference is that the column name needs to be written twice after change, which is inconvenient. But the advantage of change is that you can modify the column name, but modify cannot.

3.3. Add table field command

ALTER TABLE tablename ADD [COLUMN] column_definition [FIRST | AFTER col_name]

Example: Add a new field username to the orders table, with varchar(3) type:

mysql> alter table orders add column username varchar(30);
Query OK, 0 rows affected (0.39 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> desc orders;
+-------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------+------+-----+---------+-------+
| ordername | varchar(20) | YES | | NULL | |
| createtime | date | YES | | NULL | |
| ordermoney | decimal(10,2) | YES | | NULL | |
| ordernumber | int(2) | YES | | NULL | |
| username | varchar(30) | YES | | NULL | |
+-------------+---------------+------+-----+---------+-------+
5 rows in set (0.00 sec)

3.4. Delete table column field command

ALTER TABLE tablename DROP [COLUMN] col_name

Example: Delete username field from the orders table:

mysql> alter table orders drop column username;
Query OK, 0 rows affected (0.53 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> desc orders;
+-------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------+------+-----+---------+-------+
| ordername | varchar(20) | YES | | NULL | |
| createtime | date | YES | | NULL | |
| ordermoney | decimal(10,2) | YES | | NULL | |
| ordernumber | int(2) | YES | | NULL | |
+-------------+---------------+------+-----+---------+-------+
4 rows in set (0.00 sec)

3.5. Table rename command

ALTER TABLE tablename RENAME [TO] new_tablename

Example: The name of the table orders is changed goodsorders

mysql> alter table orders rename goodsorders;
Query OK, 0 rows affected (0.16 sec)

mysql> desc orders;
ERROR 1146 (42S02): Table 'ordermanage.orders' doesn't exist
mysql> desc goodsorders;
+--------------+---------------+-----+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------+---------------+-----+-----+---------+-------+
| ordername | varchar(20) | YES | | NULL | |
| createtime | date | YES | | NULL | |
| ordermoney | decimal(10,2) | YES | | NULL | |
| ordernumbers | int(4) | YES | | NULL | |
+--------------+---------------+-----+-----+---------+-------+
4 rows in set (0.00 sec)

4. DML statements

insert , select , update , delete

4.1. Insert record command

INSERT INTO tablename (field1,field2,...fieldn) VALUES (value1,value2,...valuesn);

Example: insert a record into the goodsorders table, ordername is zhang , createtime is 2021-05-12 , ordermoney is 100.00 , ordernumbers is: 1

mysql> insert into goodsorders (ordername,createtime,ordermoney,ordernumbers) values('zhang','2021-05-12',100.00,1);
Query OK, 1 row affected (0.03 sec)

You can also omit the (field1, field2, ... fieldn) part

mysql> insert into goodsorders values('zhang1','2021-05-12',1001.00,11);
Query OK, 1 row affected (0.05 sec)

4.2. View the insert data command

4.2.1、Query all

SELECT * FROM tablename [WHERE CONDITION]

Example: View all inserted data in goodsorders

mysql> select * from goodsorders;
+-----------+------------+------------+--------------+
| ordername | createtime | ordermoney | ordernumbers |
+-----------+------------+------------+--------------+
| zhang | 2021-05-12 | 100.00 | 1 |
| zhang1 | 2021-05-12 | 1001.00 | 11 |
+-----------+------------+------------+--------------+
2 rows in set (0.00 sec)

The "*" indicates that all records should be selected.

4.2.2. Query unique record command keywords

distinct

Example: Query the data of non-repeated creation time (createtime) in non- goodsorders

mysql> select * from goodsorders;
+-----------+------------+------------+--------------+
| ordername | createtime | ordermoney | ordernumbers |
+-----------+------------+------------+--------------+
| zhang | 2021-03-11 | 50.00 | 1 |
| li | 2020-05-12 | 70.00 | 15 |
| li | 2020-03-12 | 70.00 | 15 |
| li | 2020-03-11 | 70.00 | 15 |
| li | 2021-03-11 | 70.00 | 15 |
+-----------+------------+------------+--------------+
5 rows in set (0.00 sec)

mysql> select distinct createtime from goodsorders;
+------------+
| createtime |
+------------+
| 2021-03-11 |
| 2020-05-12 |
| 2020-03-12 |
| 2020-03-11 |
+------------+
4 rows in set (0.00 sec)

From this we can see that the duplicate time data 2021-03-11 has been removed

4.2.3. Multiple-condition query keywords

The condition after where is a field's '=' comparison, and you can also use comparison operators such as >, <, >=, <=, !=, etc.
You can also use logical operators such as or and and to perform multi-condition joint queries between multiple conditions.

Example: Query non- goodsorders where ordername='li' and createtime is 2020-03-11

mysql> select * from goodsorders where ordername='li'and createtime ='2020-03-11';
+-----------+------------+------------+--------------+
| ordername | createtime | ordermoney | ordernumbers |
+-----------+------------+------------+--------------+
| li | 2020-03-11 | 70.00 | 15 |
+-----------+------------+------------+--------------+
1 row in set (0.00 sec)

4.2.4, Sorting query naming

SELECT * FROM tablename [WHERE CONDITION] [ORDER BY field1 [DESC|ASC] ， field2 
[DESC|ASC], ...fieldn [DESC|ASC]]

Example: Sort the records in the goodsorders table by creation time

mysql> select * from goodsorders order by createtime;
+-----------+------------+------------+--------------+
| ordername | createtime | ordermoney | ordernumbers |
+-----------+------------+------------+--------------+
| li | 2020-03-11 | 70.00 | 15 |
| li | 2020-03-12 | 70.00 | 15 |
| li | 2020-05-12 | 70.00 | 15 |
| zhang | 2021-03-11 | 50.00 | 1 |
| li | 2021-03-11 | 70.00 | 15 |
+-----------+------------+------------+--------------+
5 rows in set (0.01 sec)

4.2.5. Display part, not all, of the instructions

SELECT ... [LIMIT offset_start, row_count]

offset_start indicates the starting offset of the record
row_count indicates the number of rows displayed

Example 1 : Display the first 3 records in goodsorders table sorted by createtiem :

mysql> select * from goodsorders order by createtime limit 3;
+-----------+------------+------------+--------------+
| ordername | createtime | ordermoney | ordernumbers |
+-----------+------------+------------+--------------+
| li | 2020-03-11 | 70.00 | 15 |
| li | 2020-03-12 | 70.00 | 15 |
| li | 2020-05-12 | 70.00 | 15 |
+-----------+------------+------------+--------------+
3 rows in set (0.00 sec)

Example 2: If you want to display 3 records starting from the second record in goodsorders table sorted by createtiem :

mysql> select * from goodsorders order by createtime limit 2,3;
+-----------+------------+------------+--------------+
| ordername | createtime | ordermoney | ordernumbers |
+-----------+------------+------------+--------------+
| li | 2020-05-12 | 70.00 | 15 |
| zhang | 2021-03-11 | 50.00 | 1 |
| li | 2021-03-11 | 70.00 | 15 |
+-----------+------------+------------+--------------+
3 rows in set (0.00 sec)

4.2.6. Statistics, Aggregation Instructions

SELECT [field1,field2,…fieldn] fun_name 
FROM tablename
[WHERE where_contition]
[GROUP BY field1, field2, ... fieldn
[WITH ROLLUP]]
[HAVING where_contition]

Parameter Description:

1. fun_name indicates the aggregation operation to be performed, that is, the aggregation function. Commonly used ones are sum (sum), count (*) (number of records), max (maximum value), min (minimum value)
2. GROUP BY keyword indicates the field to be classified and aggregated. For example, if you want to count the number of employees by department, the department should be written after group by.
3. WITH ROLLUP is an optional syntax that indicates whether to re-aggregate the results after classification aggregation.
4. The HAVING keyword indicates that the classified results are further filtered by conditions.

Note: The difference between having and where is that having is to filter the results after aggregation, while where is to filter the records before aggregation. If the logic allows, we should use where to filter the records first. This will greatly improve the efficiency of aggregation because the result set is reduced. Finally, we can see whether to use having for further filtering based on the logic.

Example 1: Query and count the total number of records in the goodsorders table

mysql> select count(1) from goodsorders;
+----------+
| count(1) |
+----------+
| 5 |
+----------+
1 row in set (0.00 sec)

Example 2: On this basis, group statistics by creation date ( createtime )

mysql> select createtime,count(1) from goodsorders group by createtime;
+------------+----------+
| createtime | count(1) |
+------------+----------+
| 2020-03-11 | 1 |
| 2020-03-12 | 1 |
| 2020-05-12 | 1 |
| 2021-03-11 | 2 |
+------------+----------+
4 rows in set (0.00 sec)

Example 3: On this basis, we need to group and count by creation date ( cretetime ) and calculate the total number

mysql> select createtime,count(1) from goodsorders group by createtime with rollup;
+------------+----------+
| createtime | count(1) |
+------------+----------+
| 2020-03-11 | 1 |
| 2020-03-12 | 1 |
| 2020-05-12 | 1 |
| 2021-03-11 | 2 |
| NULL | 5 |
+------------+----------+
5 rows in set (0.02 sec)

The number displayed by null in the last row is the total number.

Example 4: Group and count by createtime date (createtime), and the number is greater than 1

mysql> select createtime,count(1) from goodsorders group by createtime having count(1)>1;
+------------+----------+
| createtime | count(1) |
+------------+----------+
| 2021-03-11 | 2 |
+------------+----------+
1 row in set (0.00 sec)

Example 5: Query the total amount, minimum amount, and maximum amount of the order amount ( ordermoney ) in goodsorders table

mysql> select * from goodsorders;
+-----------+------------+------------+--------------+
| ordername | createtime | ordermoney | ordernumbers |
+-----------+------------+------------+--------------+
| zhang | 2021-03-11 | 50.00 | 1 |
| li | 2020-05-12 | 70.00 | 15 |
| li | 2020-03-12 | 70.00 | 15 |
| li | 2020-03-11 | 70.00 | 15 |
| li | 2021-03-11 | 70.00 | 15 |
+-----------+------------+------------+--------------+
5 rows in set (0.00 sec)

mysql> select sum(ordermoney),max(ordermoney),min(ordermoney) from goodsorders;
+-----------------+-----------------+-----------------+
| sum(ordermoney) | max(ordermoney) | min(ordermoney) |
+-----------------+-----------------+-----------------+
| 330.00 | 70.00 | 50.00 |
+-----------------+-----------------+-----------------+
1 row in set (0.02 sec)

4.2.7. Table Join

1. Left join: includes all records in the left table, even those that do not match the right table; key command: left left join
2. Right join: includes all records in the right table, even those that do not match the left table; association instruction: right join

Example 1: Now we create another user table ( member ), use goodorders to perform a left join, and query the associated user table information

mysql> select * from member;
+------+------------+
| id | membername |
+------+------------+
| 15 | zhang |
| 1 | li |
| 13 | liss |
+------+------------+
3 rows in set (0.00 sec)

mysql> select * from goodsorders;
+-----------+------------+------------+--------------+----------+
| ordername | createtime | ordermoney | ordernumbers | memberid |
+-----------+------------+------------+--------------+----------+
| zhang | 2021-03-11 | 50.00 | 1 | 15 |
| li | 2020-05-12 | 70.00 | 15 | 1 |
| li | 2020-03-12 | 70.00 | 15 | 1 |
| li | 2020-03-11 | 70.00 | 15 | 3 |
| li | 2021-03-11 | 70.00 | 15 | 1 |
+-----------+------------+------------+--------------+----------+
5 rows in set (0.00 sec)

mysql> select * from goodsorders left join member on goodsorders.memberid = member.id;
+-----------+------------+------------+--------------+----------+------------+
| ordername | createtime | ordermoney | ordernumbers | memberid | id | membername |
+-----------+------------+------------+--------------+----------+------------+
| zhang | 2021-03-11 | 50.00 | 1 | 15 | 15 | zhang |
| li | 2020-05-12 | 70.00 | 15 | 1 | 1 | li |
| li | 2020-03-12 | 70.00 | 15 | 1 | 1 | li |
| li | 2021-03-11 | 70.00 | 15 | 1 | 1 | li |
| li | 2020-03-11 | 70.00 | 15 | 3 | NULL | NULL |
+-----------+------------+------------+--------------+----------+------------+
5 rows in set (0.00 sec)

Example 2 : The data in member and goodsorders remain unchanged. Let's take a look at the right join query and the result:

mysql> select * from goodsorders right join member on goodsorders.memberid = member.id;
+-----------+------------+------------+--------------+----------+------------+
| ordername | createtime | ordermoney | ordernumbers | memberid | id | membername |
+-----------+------------+------------+--------------+----------+------------+
| zhang | 2021-03-11 | 50.00 | 1 | 15 | 15 | zhang |
| li | 2020-05-12 | 70.00 | 15 | 1 | 1 | li |
| li | 2020-03-12 | 70.00 | 15 | 1 | 1 | li |
| li | 2021-03-11 | 70.00 | 15 | 1 | 1 | li |
| NULL | NULL | NULL | NULL | NULL | 13 | liss |
+-----------+------------+------------+--------------+----------+------------+
5 rows in set (0.00 sec)

A reversal has occurred here, and a data entry in goodsorders table on the left is empty.

4.2.8. Subqueries, related keywords

Mainly includes in , not in , = , != , exists , not exists , etc.

Example: Query all users' records in the members table from goodsorders table

mysql> select * from member;
+------+------------+
| id | membername |
+------+------------+
| 15 | zhang |
| 1 | li |
| 13 | liss |
+------+------------+
3 rows in set (0.00 sec)

mysql> select * from goodsorders;
+-----------+------------+------------+--------------+----------+
| ordername | createtime | ordermoney | ordernumbers | memberid |
+-----------+------------+------------+--------------+----------+
| zhang | 2021-03-11 | 50.00 | 1 | 15 |
| li | 2020-05-12 | 70.00 | 15 | 1 |
| li | 2020-03-12 | 70.00 | 15 | 1 |
| li | 2020-03-11 | 70.00 | 15 | 3 |
| li | 2021-03-11 | 70.00 | 15 | 1 |
+-----------+------------+------------+--------------+----------+
5 rows in set (0.00 sec)

mysql> select * from goodsorders where memberid in(select id from member);
+-----------+------------+------------+--------------+----------+
| ordername | createtime | ordermoney | ordernumbers | memberid |
+-----------+------------+------------+--------------+----------+
| zhang | 2021-03-11 | 50.00 | 1 | 15 |
| li | 2020-05-12 | 70.00 | 15 | 1 |
| li | 2020-03-12 | 70.00 | 15 | 1 |
| li | 2021-03-11 | 70.00 | 15 | 1 |
+-----------+------------+------------+--------------+----------+
4 rows in set (0.05 sec)

4.2.9. Recording Joint Instructions

SELECT * FROM t1
UNION|UNION ALL
SELECT * FROM t2
…
UNION|UNION ALL
SELECT * FROM tn;

The main differences between UNION and UNION ALL :

UNION ALL directly merges the result sets together.
UNION performs a DISTINCT on the result of UNION ALL to remove duplicate records.

Example 1: Display the set of user id (memberid) in the member table and goodsorders table

mysql> select memberid from goodsorders union all select id from member;
+----------+
| memberid |
+----------+
| 15 |
| 1 |
| 1 |
| 3 |
| 1 |
| 15 |
| 1 |
| 13 |
+----------+
8 rows in set (0.00 sec)

Example 2: If you want to remove duplicate records from the above results and display

mysql> select memberid from goodsorders union select id from member;
+----------+
| memberid |
+----------+
| 15 |
| 1 |
| 3 |
| 13 |
+----------+
4 rows in set (0.00 sec)

4.3. Update record command

UPDATE tablename SET field1=value1，field2.=value2，…fieldn=valuen [WHERE CONDITION]

Example: Change the order amount ( ordermoney ) of ordername zhang in goodsorders table 50

mysql> update goodsorders set ordermoney=50.00 where ordername='zhang';
Query OK, 1 row affected (0.09 sec)
Rows matched: 1 Changed: 1 Warnings: 0

mysql> select * from goodsorders;
+-----------+------------+------------+--------------+
| ordername | createtime | ordermoney | ordernumbers |
+-----------+------------+------------+--------------+
| zhang | 2021-05-12 | 50.00 | 1 |
| zhang1 | 2021-05-12 | 1001.00 | 11 |
+-----------+------------+------------+--------------+
2 rows in set (0.00 sec)

When updating, if you encounter error code 1175:

Error Code: 1175. You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. To disable safe mode, toggle the option in Preferences

Solution:

1. First query the status:

show variables like 'SQL_SAFE_UPDATES';

2. Execute the following SQL to turn off safe-updates mode:

SET SQL_SAFE_UPDATES = 0;

SET SQL_SAFE_UPDATES = false;

4.4. Delete record naming

DELETE FROM tablename [WHERE CONDITION]

Example: Delete all records whose ordername is zhang1 in the goodsorders table

mysql> delete from goodsorders where ordername = 'zhang1';
Query OK, 1 row affected (0.06 sec)

mysql> select * from goodsorders;
+-----------+------------+------------+--------------+
| ordername | createtime | ordermoney | ordernumbers |
+-----------+------------+------------+--------------+
| zhang | 2021-05-12 | 50.00 | 1 |
+-----------+------------+------------+--------------+
1 row in set (0.02 sec)

4.5. Initialization table

Example: Clear all data in a table

mysql> select * from varc;
+------+------+
| v | c |
+------+------+
| abc | abc |
+------+------+
1 row in set (0.03 sec)

mysql> truncate table varc;
Query OK, 0 rows affected (0.25 sec)

mysql> select * from varc;
Empty set (0.00 sec)

5. DCL Statements

DCL statements are mainly used to manage the permissions of operation objects in the database system

5.1 Create a database user

Example: Create a database user named user1 with an initial password of 123 and SELECT/INSERT permissions for all tables in the ordermanage database:

mysql> grant select,insert on ordermanage.* to 'user1'@'localhost' identified by '123';
Query OK, 0 rows affected, 1 warning (0.06 sec)

mysql> exit
Bye


C:\Program Files\MySQL\MySQL Server 5.7\bin>mysql -uuser1 -p123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 82
Server version: 5.7.17-log MySQL Community Server (GPL)

Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
|ordermanage|
+--------------------+
2 rows in set (0.00 sec)

On this basis, the insert permission of this user ( user1 ) is revoked

mysql> revoke insert on ordermanage.* from 'user1'@'localhost';
Query OK, 0 rows affected (0.02 sec)

mysql> exit
Bye

C:\Program Files\MySQL\MySQL Server 5.7\bin>mysql -uuser1 -p123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 84
Server version: 5.7.17-log MySQL Community Server (GPL)

Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> use ordermanage;
Database changed

mysql> insert into member values('11','ss');
ERROR 1142 (42000): INSERT command denied to user 'user1'@'localhost' for table 'member'
mysql>

It can be seen from this that the insertion permission is insufficient and the insertion fails

This is the end of this article about the introduction of MYSQL tables. For more relevant MYSQL table content, please search for previous articles on 123WORDPRESS.COM or continue to browse the following related articles. I hope everyone will support 123WORDPRESS.COM in the future!

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