Det følgende er ret hurtigt, tager lidt over 6 minutter med 10 millioner rækker, men eksempeltabellen har færre felter og indekser end din produktionstabel, så forvent, at det tager lidt længere tid i dit tilfælde, hvis du beslutter dig for at bruge det!
Bemærk:eksemplet blev lavet på Windows OS, så du bliver nødt til at ændre stinavne og \r\n til \n for at overholde linux-standarderne!
Her er min eksisterende tabel (InnoDB-motor):
drop table if exists customers;
create table customers
(
customer_id int unsigned not null auto_increment primary key,
name varchar(255) not null,
country_id tinyint unsigned not null default 0,
key (country_id)
)
engine=innodb;
mysql> select count(*) from customers;
+----------+
| count(*) |
+----------+
| 10000000 |
+----------+
1 row in set (1.78 sec)
Opret en ny version af tabellen, som indeholder det nye felt, du har brug for:
drop table if exists customers_new;
create table customers_new
(
customer_id int unsigned not null auto_increment primary key,
name varchar(255) not null,
country_id tinyint unsigned not null default 0,
split tinyint not null default 0,
key (country_id)
)
engine=innodb;
Find placeringen af din upload-mappe:
select @@secure_file_priv;
Eksporter dataene i PK-rækkefølge fra den gamle kundetabel til csv-format:
select * into outfile 'C:\\ProgramData\\MySQL\\MySQL Server 8.0\\Uploads\\customers.dat'
fields terminated by '|' optionally enclosed by '"'
lines terminated by '\r\n'
from customers order by customer_id;
Query OK, 10000000 rows affected (17.39 sec)
Indlæs filen customer.dat i den nye kundetabel:
truncate table customers_new;
set autocommit = 0;
load data infile 'C:\\ProgramData\\MySQL\\MySQL Server 8.0\\Uploads\\customers.dat'
into table customers_new
fields terminated by '|' optionally enclosed by '"'
lines terminated by '\r\n'
(
customer_id,
name,
country_id,
@dummy -- represents the new split field
)
set
name = nullif(name,'');
commit;
Query OK, 10000000 rows affected (6 min 0.14 sec)
Bekræft, at den nye tabel ser ok ud:
select * from customers_new order by customer_id desc limit 1;
+-------------+-------------------+------------+-------+
| customer_id | name | country_id | split |
+-------------+-------------------+------------+-------+
| 10000000 | customer 10000000 | 218 | 0 |
+-------------+-------------------+------------+-------+
1 row in set (0.00 sec)
insert into customers_new (name, country_id, split) values ('f00',1,1);
Query OK, 1 row affected (0.07 sec)
select * from customers_new order by customer_id desc limit 1;
+-------------+------+------------+-------+
| customer_id | name | country_id | split |
+-------------+------+------------+-------+
| 10000001 | f00 | 1 | 1 |
+-------------+------+------------+-------+
1 row in set (0.00 sec)
Slip den gamle tabel og omdøb den nye:
drop table customers;
Query OK, 0 rows affected (0.18 sec)
rename table customers_new to customers;
Query OK, 0 rows affected (0.05 sec)
select * from customers order by customer_id desc limit 1;
+-------------+------+------------+-------+
| customer_id | name | country_id | split |
+-------------+------+------------+-------+
| 10000001 | f00 | 1 | 1 |
+-------------+------+------------+-------+
1 row in set (0.00 sec)
Det er det hele folkens!