Differences between revisions 5 and 6
Revision 5 as of 2007-06-16 01:03:28
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Revision 6 as of 2007-06-16 01:10:55
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Editor: DavidJoyner
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Deletions are marked like this. Additions are marked like this.
Line 14: Line 14:
conn = sqlite3.connect("/full/path/mydata.db") sage: conn = sqlite3.connect("/full/path/mydata.db")
Line 21: Line 21:
connection.execute("...")
sage: connection.execute("CREATE TABLE cremona_label text primary key, a_0 int, a_1 int, a_2 int, a_3 int, a_4 int, a_5 int, a_6 int, rank int, regulator float)")
Line 28: Line 27:
E = EllipticCurve("389a")
connection.execute("...")
sage: E = EllipticCurve("389a")
sage: connection.execute("INSERT INTO elliptic_curves(cremona_label,a_0,a_1,a_2,a_3,a_4,a_5,a_6,rank,regulator) VALUES (?,?,?,?,?,?,?,?,?,?)", ("389a",0,E.a1(),E.a2(),E.a3(),E.a4(),0,E.a6(),E.rank(),E.regular()))
Line 36: Line 35:
{{{
sage: connection.execute("DELETE FROM elliptic_curves WHERE cremona_label = ?",("389a",))
Line 39: Line 40:
result = connection.execute("SELECT * FROM elliptic_curves WHERE rank = 2")
result.fetchone()
sage: result = connection.execute("SELECT * FROM elliptic_curves WHERE rank = 2")
sage: result.fetchone()

Tom Boothby's sqlite-tutorial

How to create a simple database in sqlite using SAGE.

In SAGE, type

sage: import sqlite3

To create a filename for the database

sage: conn = sqlite3.connect("/full/path/mydata.db")

This is a blank database at the moment. Now create a table with fields labeled/typed as follows:

sage: connection.execute("CREATE TABLE cremona_label text primary key, a_0 int, a_1 int, a_2 int, a_3 int, a_4 int, a_5 int, a_6 int,  rank int, regulator float)")

This creates a sqlite3.cursor object. Now let's enter an entry into this database

sage: E = EllipticCurve("389a")
sage: connection.execute("INSERT INTO elliptic_curves(cremona_label,a_0,a_1,a_2,a_3,a_4,a_5,a_6,rank,regulator) VALUES (?,?,?,?,?,?,?,?,?,?)", ("389a",0,E.a1(),E.a2(),E.a3(),E.a4(),0,E.a6(),E.rank(),E.regular()))

This is our new entry in the database mydata!

Suppose you entered something wrong and you want to delete an entry. You use the primary key to delete an entry:

sqlite-tutorial (last edited 2008-11-14 13:42:00 by anonymous)