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URL:: http://sqlite.org/
  licence:: Sources are uncopyrighted. Use for any purpose.
  platforms:: Built and tested under Linux and Win2K.
 URL:: http://sqlite.org/
 licence:: Sources are uncopyrighted. Use for any purpose.
 platforms:: Built and tested under Linux and Win2K.
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URL:: http://pysqlite.org/
  SourceForge:: http://sourceforge.net/projects/pysqlite
  licence:: zlib/libpng License
  platforms:: Windows 95/98/2000/XP, POSIX, MacOS X
  Python versions:: 2.1 or later (1.x branch)/2.3 or later (2.0 branch)
 URL:: http://pysqlite.org/
 SourceForge:: http://sourceforge.net/projects/pysqlite
 licence:: zlib/libpng License
 platforms:: Windows 95/98/2000/XP, POSIX, MacOS X
 Python versions:: 2.1 or later (1.x branch)/2.3 or later (2.0 branch). Included in Python 2.5.
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* Extensible type conversion
  * Factories for connection and cursor objects
  * row converter factory to easily and efficiently switch to a nonstandard type for rows (e. g. dicts)
  * User-defined functions and aggregates
 * Extensible type conversion
 * Factories for connection and cursor objects
 * row converter factory to easily and efficiently switch to a nonstandard type for rows (e. g. dicts)
 * User-defined functions and aggregates
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URL:: http://www.rogerbinns.com/apsw.html
  licence:: zlib/libpng license
  platforms:: Windows, POSIX
  Python versions:: ?
 URL:: http://www.rogerbinns.com/apsw.html
 licence:: zlib/libpng license
 platforms:: Windows, POSIX
 Python versions:: ?
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 * it's extensible in a very easy way via Python   * it's extensible in a very easy way via Python
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== Usage Notes ==
The following solution was difficult to discover with the available documentation (http://pysqlite.org/ was unavailable). If this page can be found by others searching for answers, it may save many hours of frustration.

=== Id of Most Recent Row ===
After creating a new row in a table that uses AUTOINCREMENT to create the PRIMARY KEY, one may wish to determine the value of the new row-id, for example if the value is need for a new row in a related table that will be inserted next. The answer is to use the ''lastrowid'' property of the ''cursor'' class as in {{{newId=c.lastrowid }}} shown below in a demo context. Tested in Python2.5.1 with the sqlite3 module:

{{{
           import sqlite3
           con = sqlite3.connect('demo.db')
           con.execute("""CREATE TABLE tbl (
               id INTEGER PRIMARY KEY AUTOINCREMENT,
               grp INTEGER)""")
           c = con.cursor()
           c.execute("""INSERT INTO tbl (grp) VALUES (0);""")

           newId = c.lastrowid

           print "New rowid =", newId
           c.close()
           con.close()
}}}
The result is printed:{{{ New rowid = 1}}}

TableOfContents

Masthead

URL

http://sqlite.org/

licence
Sources are uncopyrighted. Use for any purpose.
platforms
Built and tested under Linux and Win2K.

DB API 2.0 Drivers

pysqlite

URL

http://pysqlite.org/

SourceForge

http://sourceforge.net/projects/pysqlite

licence
zlib/libpng License
platforms
Windows 95/98/2000/XP, POSIX, MacOS X
Python versions
2.1 or later (1.x branch)/2.3 or later (2.0 branch). Included in Python 2.5.

Extensions to DB API

  • Extensible type conversion
  • Factories for connection and cursor objects
  • row converter factory to easily and efficiently switch to a nonstandard type for rows (e. g. dicts)
  • User-defined functions and aggregates

Comments

Other Drivers

APSW

URL

http://www.rogerbinns.com/apsw.html

licence
zlib/libpng license
platforms
Windows, POSIX
Python versions
?

Programming Model

APSW is a SQLite 3 wrapper that provides a thin layer over SQLite 3. Although APSW looks vaguely similar to the DBAPI, it is not compliant with that API and instead mirrors the way SQLite 3 works.

Comments

Supported Python Applications

  • Thuban (GIS application)
  • Roundup (issue tracker)
  • PyPI (Python Package Index)
  • Trac (issue tracker, wiki, Subversion web frontend)
  • Cloud Wiki (wiki)
  • Supybot (IRC bot framework)
  • PyAddbook (Address Book)

Pros

I think SQLite may be a good replacement for gadfly, because:

  • the main engine is written in C, so it should be faster than the gadfly implementation in Python
  • it's extensible in a very easy way via Python
  • it doesn't put all data in memory like gadfly does (yet you can do that if you want, just use ':memory:' as filename
  • It's very cool for small databased application, because you do not have to start an external DBMS
  • Implements almost all of SQL92

Cons

  • SQLite only supports the basic types NULL, INTEGER, FLOAT, TEXT and BLOB
  • If you want to use other types like DATE and TIME in pysqlite, you need to use its "pysqlite types mode", where things can get a little nastier.

Usage Notes

The following solution was difficult to discover with the available documentation (http://pysqlite.org/ was unavailable). If this page can be found by others searching for answers, it may save many hours of frustration.

Id of Most Recent Row

After creating a new row in a table that uses AUTOINCREMENT to create the PRIMARY KEY, one may wish to determine the value of the new row-id, for example if the value is need for a new row in a related table that will be inserted next. The answer is to use the lastrowid property of the cursor class as in newId=c.lastrowid  shown below in a demo context. Tested in Python2.5.1 with the sqlite3 module:

           import sqlite3
           con = sqlite3.connect('demo.db')
           con.execute("""CREATE TABLE tbl (
               id INTEGER PRIMARY KEY AUTOINCREMENT,
               grp INTEGER)""")
           c = con.cursor()
           c.execute("""INSERT INTO tbl (grp) VALUES (0);""")

           newId = c.lastrowid

           print "New rowid =", newId
           c.close()
           con.close()

The result is printed: New rowid = 1

SQLite (last edited 2012-01-30 07:26:58 by 50-0-67-239)

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