! Copyright (C) 2008 Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: classes kernel help.markup help.syntax sequences
-alien assocs strings math multiline quotations db.private ;
+alien assocs strings math quotations db.private ;
IN: db
HELP: db-connection
{ $subsection sql-query }
"Here's an example usage where we'll make a book table, insert some objects, and query them." $nl
"First, let's set up a custom combinator for using our database. See " { $link "db-custom-database-combinators" } " for more details."
-{ $code <"
+{ $code "
USING: db.sqlite db io.files io.files.temp ;
: with-book-db ( quot -- )
- "book.db" temp-file <sqlite-db> swap with-db ; inline"> }
+ "book.db" temp-file <sqlite-db> swap with-db ; inline" }
"Now let's create the table manually:"
-{ $code <" "create table books
+{ $code " "create table books
(id integer primary key, title text, author text, date_published timestamp,
edition integer, cover_price double, condition text)"
- [ sql-command ] with-book-db"> }
+ [ sql-command ] with-book-db" }
"Time to insert some books:"
-{ $code <"
+{ $code "
"insert into books
(title, author, date_published, edition, cover_price, condition)
values('Factor for Sheeple', 'Mister Stacky Pants', date('now'), 1, 13.37, 'mint')"
-[ sql-command ] with-book-db"> }
+[ sql-command ] with-book-db" }
"Now let's select the book:"
-{ $code <"
-"select id, title, cover_price from books;" [ sql-query ] with-book-db "> }
+{ $code "
+"select id, title, cover_price from books;" [ sql-query ] with-book-db " }
"Notice that the result of this query is a Factor array containing the database rows as arrays of strings. We would have to convert the " { $snippet "cover_price" } " from a string to a number in order to use it in a calculation." $nl
"In conclusion, this method of accessing a database is supported, but it is fairly low-level and generally specific to a single database. The " { $vocab-link "db.tuples" } " vocabulary is a good alternative to writing SQL by hand." ;
"Make a " { $snippet "with-" } " combinator to open and close a database so that resources are not leaked." $nl
"SQLite example combinator:"
-{ $code <"
+{ $code "
USING: db.sqlite db io.files io.files.temp ;
: with-sqlite-db ( quot -- )
- "my-database.db" temp-file <sqlite-db> swap with-db ; inline"> }
+ "my-database.db" temp-file <sqlite-db> swap with-db ; inline" }
"PostgreSQL example combinator:"
-{ $code <" USING: db.postgresql db ;
+{ $code " USING: db.postgresql db ;
: with-postgresql-db ( quot -- )
<postgresql-db>
"localhost" >>host
"erg" >>username
"secrets?" >>password
"factor-test" >>database
- swap with-db ; inline">
+ swap with-db ; inline"
} ;
ABOUT: "db"