After creating your table, you need to populate it. The
LOAD DATA and INSERT statements are useful for this. Suppose that your pet records can be described as shown here. (Observe that MySQL expects dates in
'YYYY-MM-DD' format; this may be different from what you are used to.) | name | owner | species | sex | birth | death |
| Fluffy | Harold | cat | f | 1993-02-04 | |
| Claws | Gwen | cat | m | 1994-03-17 | |
| Buffy | Harold | dog | f | 1989-05-13 | |
| Fang | Benny | dog | m | 1990-08-27 | |
| Bowser | Diane | dog | m | 1979-08-31 | 1995-07-29 |
| Chirpy | Gwen | bird | f | 1998-09-11 | |
| Whistler | Gwen | bird | 1997-12-09 | ||
| Slim | Benny | snake | m | 1996-04-29 |
You could create a text file
pet.txt containing one record per line, with values separated by tabs, and given in the order in which the columns were listed in the CREATE TABLE statement. For missing values (such as unknown sexes or death dates for animals that are still living), you can use NULL values. To represent these in your text file, use \N (backslash, capital-N). For example, the record for Whistler the bird would look like this (where the whitespace between values is a single tab character): Whistler Gwen bird \N 1997-12-09 \NTo load the text file
pet.txt into the pet table, use this statement: mysql> LOAD DATA LOCAL INFILE '/path/pet.txt' INTO TABLE pet;
If you created the file on Windows with an editor that uses \r\n as a line terminator, you should use this statement instead: mysql>(On an Apple machine running OS X, you would likely want to useLOAD DATA LOCAL INFILE '/path/pet.txt' INTO TABLE pet->LINES TERMINATED BY '\r\n';
LINES TERMINATED BY '\r'.) You can specify the column value separator and end of line marker explicitly in the
LOAD DATA statement if you wish, but the defaults are tab and linefeed. These are sufficient for the statement to read the file pet.txt properly. If the statement fails, it is likely that your MySQL installation does not have local file capability enabled by default. See “Security Issues with
LOAD DATA LOCAL”, for information on how to change this. When you want to add new records one at a time, the
INSERT statement is useful. In its simplest form, you supply values for each column, in the order in which the columns were listed in the CREATE TABLE statement. Suppose that Diane gets a new hamster named “Puffball.” You could add a new record using an INSERT statement like this: mysql>String and date values are specified as quoted strings here. Also, withINSERT INTO pet->VALUES ('Puffball','Diane','hamster','f','1999-03-30',NULL);
INSERT, you can insert NULL directly to represent a missing value. You do not use \N like you do with LOAD DATA. From this example, you should be able to see that there would be a lot more typing involved to load your records initially using several
INSERT statements rather than a single LOAD DATA statement.
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