Importing Data with LOAD DATA and mysqlimport

10.2.1 Problem

You want to load a datafile into a table using MySQL's built in import capabilities.

10.2.2 Solution

Use the LOAD DATA statement or the mysqlimport command-line program.

10.2.3 Discussion

MySQL provides a LOAD DATA statement that acts as a bulk data loader. Here's an example statement that reads a file mytbl.txt from your current directory and loads it into the table mytbl in the current database:

mysql> LOAD DATA LOCAL INFILE 'mytbl.txt' INTO TABLE mytbl;

MySQL also includes a utility program named mysqlimport that acts as a wrapper around LOAD DATA so that you can load input files directly from the command line. The mysqlimport command that is equivalent to the preceding LOAD DATA statement looks like this, assuming that mytbl is in the cookbook database:[1]

[1] For mysqlimport, as with other MySQL programs, you may need to specify connection parameter options such as --user or --host. If so, they should precede the database name argument.

% mysqlimport --local cookbook mytbl.txt

The following list describes LOAD DATA's general characteristics and capabilities; mysqlimport shares most of these behaviors. There are some differences that we'll note as we go along, but for the most part you can read "LOAD DATA" as "LOAD DATA or mysqlimport." LOAD DATA provides options to address many of the import issues mentioned in the chapter introduction, such as the line-ending sequence for recognizing how to break input into records, the column value delimiter that allows records to be broken into separate values, the quoting character that may surround column values, quoting and escaping issues within values, and NULL value representation:

The next few sections describe how to import datafiles into MySQL tables using LOAD DATA or mysqlimport. They assume your files contain legal data values that are acceptable to MySQL. Why make this assumption? Because although LOAD DATA has several options that control how it reads the datafile, they're concerned only with the structure of the file. LOAD DATA won't validate or reformat data values for you. It's necessary to perform such operations either by preprocessing the datafile before loading it, or by issuing SQL statements after loading it. If you need to check or reformat an input file first to make sure it's legal, several sections later in the chapter show how to do that.

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