get nearby stations from sqlite3 db

[pywienerlinien] / gotovienna / sqlite3 / dump.py

diff --git a/gotovienna/sqlite3/dump.py b/gotovienna/sqlite3/dump.py
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+# Mimic the sqlite3 console shell's .dump command
+# Author: Paul Kippes <kippesp@gmail.com>
+
+def _iterdump(connection):
+    """
+    Returns an iterator to the dump of the database in an SQL text format.
+
+    Used to produce an SQL dump of the database.  Useful to save an in-memory
+    database for later restoration.  This function should not be called
+    directly but instead called from the Connection method, iterdump().
+    """
+
+    cu = connection.cursor()
+    yield('BEGIN TRANSACTION;')
+
+    # sqlite_master table contains the SQL CREATE statements for the database.
+    q = """
+        SELECT name, type, sql
+        FROM sqlite_master
+            WHERE sql NOT NULL AND
+            type == 'table'
+        """
+    schema_res = cu.execute(q)
+    for table_name, type, sql in schema_res.fetchall():
+        if table_name == 'sqlite_sequence':
+            yield('DELETE FROM sqlite_sequence;')
+        elif table_name == 'sqlite_stat1':
+            yield('ANALYZE sqlite_master;')
+        elif table_name.startswith('sqlite_'):
+            continue
+        # NOTE: Virtual table support not implemented
+        #elif sql.startswith('CREATE VIRTUAL TABLE'):
+        #    qtable = table_name.replace("'", "''")
+        #    yield("INSERT INTO sqlite_master(type,name,tbl_name,rootpage,sql)"\
+        #        "VALUES('table','%s','%s',0,'%s');" %
+        #        qtable,
+        #        qtable,
+        #        sql.replace("''"))
+        else:
+            yield('%s;' % sql)
+
+        # Build the insert statement for each row of the current table
+        res = cu.execute("PRAGMA table_info('%s')" % table_name)
+        column_names = [str(table_info[1]) for table_info in res.fetchall()]
+        q = "SELECT 'INSERT INTO \"%(tbl_name)s\" VALUES("
+        q += ",".join(["'||quote(" + col + ")||'" for col in column_names])
+        q += ")' FROM '%(tbl_name)s'"
+        query_res = cu.execute(q % {'tbl_name': table_name})
+        for row in query_res:
+            yield("%s;" % row[0])
+
+    # Now when the type is 'index', 'trigger', or 'view'
+    q = """
+        SELECT name, type, sql
+        FROM sqlite_master
+            WHERE sql NOT NULL AND
+            type IN ('index', 'trigger', 'view')
+        """
+    schema_res = cu.execute(q)
+    for name, type, sql in schema_res.fetchall():
+        yield('%s;' % sql)
+
+    yield('COMMIT;')