tdbc_sqlite3
Name
tdbc::sqlite3 — TDBC driver for the SQLite3 database manager
Synopsis
package require
tdbc::sqlite3 1.0 tdbc::sqlite3::connection create db fileName ?
-option value...?
Description
The
tdbc::sqlite3 driver provides a database interface that conforms to Tcl DataBase Connectivity (TDBC) and allows a Tcl script to connect to a SQLite3 database. It is also provided as a worked example of how to write a database driver in Tcl, so that driver authors have a starting point for further development.
Connection to a SQLite3 database is established by invoking tdbc::sqlite3::connection create, passing it a string to be used as the connection handle followed by the file name of the database. The side effect of tdbc::sqlite3::connection create is to create a new database connection.. As an alternative, tdbc::sqlite::connection new may be used to create a database connection with an automatically assigned name. The return value from tdbc::sqlite::connection new is the name that was chosen for the connection handle. See tdbc::connection(n) for the details of how to use the connection to manipulate a database.
Configuration options
The standard configuration options
-encoding,
-isolation,
-readonly and
-timeout are all recognized, both on
tdbc::sqlite3::connection create and on the
configure method of the resulting connection.
Since the encoding of a SQLite3 database is always well known, the -encoding option accepts only utf-8 as an encoding and always returns utf-8 for an encoding. The actual encoding may be set using a SQLite3 PRAGMA statement when creating a new database.
Only the isolation levels readuncommitted and serializable are implemented. Other isolation levels are promoted to serializable.
The -readonly flag is not implemented. -readonly 0 is accepted silently, while -readonly 1 reports an error.
Bugs
If any column name is not unique among the columns in a result set, the results of
-as dicts returns will be missing all but the rightmost of the duplicated columns. This limitation can be worked around by adding appropriate
AS clauses to
SELECT statements to ensure that all returned column names are unique. Plans are to fix this bug by using a C implementation of the driver, which will also improve performance significantly.
See also
tdbc,
tdbc::connection,
tdbc::resultset,
tdbc::statement Copyright
Copyright (c) 2008 by Kevin B. Kenny.