Using MySQL Shell Util import_table and import_json for Fast Data Import

Background MySQL 8.0 Shell provides two util sub‑modules, import_table (JS and Python variants) and import_json , which communicate via the classic MySQL protocol and the X Plugin protocol respectively. Traditional load data infile and mysqlimport import data single‑threaded, taking about 24 seconds for 1 000 000 rows.

Analysis The Shell util tools require local_infile to be enabled. import_table accepts a file path and an options object (schema, table, field delimiter, progress display, thread count, etc.).

Importing CSV with import_table

Example session (Python mode):

MySQL 127.0.0.1:3306 ssl Py> \c [email protected]:3306
Creating a session to '[email protected]:3306'
MySQL 127.0.0.1:3306 ssl Py> \use ytt
Default schema set to `ytt`.
MySQL 127.0.0.1:3306 ssl Py> y_file1='/var/lib/mysql-files/tl1.csv'
MySQL 127.0.0.1:3306 ssl Py> y_options1={"schema":"ytt","table":"tl1","fieldsTerminatedBy":",","showProgress":True,"threads":4}
MySQL 127.0.0.1:3306 ssl Py> util.import_table(y_file1,y_options1);
Importing from file '/var/lib/mysql-files/tl1.csv' to table `ytt`.`tl1` ...
File '/var/lib/mysql-files/tl1.csv' (40.87 MB) was imported in 16.74 sec at 2.44 MB/s

The import completed in under 17 seconds, noticeably faster than mysqlimport .

Using dialect option The dialect option can simplify the command by pre‑defining delimiters. Setting dialect":"csv-unix" yields similar performance with fewer parameters.

Importing JSON

Create a JSON table:

MySQL 127.0.0.1:3306 ssl Py> \sql create table tl1_json(
    id bigint primary key,
    content json);
Query OK, 0 rows affected

Define file and options:

MySQL 127.0.0.1:3306 ssl Py> y_file2='/var/lib/mysql-files/tl1.json'
MySQL 127.0.0.1:3306 ssl Py> rows=['content']
MySQL 127.0.0.1:3306 ssl Py> y_options2={"schema":"ytt","table":"tl1_json","dialect":"json","showProgress":True,"threads":4,'columns':rows}
MySQL 127.0.0.1:3306 ssl Py> util.import_table(y_file2,y_options2);
File '/var/lib/mysql-files/tl1.json' (90.15 MB) was imported in 23.35 sec at 3.86 MB/s

Importing JSON via the X Plugin protocol can also be done with util.import_json after switching to the X port (33060):

MySQL 127.0.0.1:33060+ ssl Py> \c [email protected]:33060
Creating a session to '[email protected]:33060'
MySQL 127.0.0.1:33060+ ssl Py> \use ytt
MySQL 127.0.0.1:33060+ ssl Py> y_options3={"schema":"ytt","table":"tl1_json","tableColumn":"content"}
MySQL 127.0.0.1:33060+ ssl Py> util.import_json(y_file2,y_options3);
Processed 90.15 MB in 1 048 576 documents in 35.24 sec

While import_json runs single‑threaded and is slower (≈35 seconds), it supports seamless conversion between BSON and JSON.

Conclusion MySQL Shell util functions provide a fast, flexible way to bulk‑load CSV and JSON data, often outperforming the classic mysqlimport tool, especially when multi‑threading and appropriate dialect options are used.