Update MySQL table from a local file

Question

I have a table in a database, and I\'d like to update a column which I have offline on a local file. The file itself has two columns

1. an ID which corresponds to

Answer 1

It depends of the no of rows , If it is in hundreds make a script of update column and run it , but if it is in large volume import that file in to a new table and update your table with a join , and then drop the table

Answer 2

I suggest you load your data into a temporary table, then use an INSERT ... SELECT ... ON DUPLICATE KEY UPDATE; for example:

CREATE TEMPORARY TABLE temptable (
  id  INT UNSIGNED NOT NULL,
  val INT,
  PRIMARY KEY (id)
) ENGINE = MEMORY;

LOAD DATA LOCAL INFILE '/path/to/file.txt' INTO temptable FIELDS TERMINATED BY ',';

INSERT INTO my_table
SELECT id, val FROM temptable
ON DUPLICATE KEY UPDATE val = VALUES(val);

DROP TEMPORARY TABLE temptable;

Answer 3

Another way could be ...

Since you already know the table name as well have the ID and actual value ... what you can do is ... directly write the update statements in a file, like

update mytable set value_col = value where ID_col = ID;

Second Update Statement

Third Update statement

.......

Save the file as *.sql like, updatescript.sql and then execute that script directly like

mysql -h <hostname> -u root -p <your_db_name> < "E:/scripts/sql/updatescript.sql"