intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 70 insertions, 0 deletions

diff --git a/contrib/tools/python3/src/Lib/sqlite3/dump.py b/contrib/tools/python3/src/Lib/sqlite3/dump.py
new file mode 100644
index 0000000000..de9c368be3
--- /dev/null
+++ b/contrib/tools/python3/src/Lib/sqlite3/dump.py
@@ -0,0 +1,70 @@
+# Mimic the sqlite3 console shell's .dump command
+# Author: Paul Kippes <kippesp@gmail.com>
+
+# Every identifier in sql is quoted based on a comment in sqlite
+# documentation "SQLite adds new keywords from time to time when it
+# takes on new features. So to prevent your code from being broken by
+# future enhancements, you should normally quote any identifier that
+# is an English language word, even if you do not have to."
+
+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'
+            ORDER BY "name"
+        """
+    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','{0}','{0}',0,'{1}');".format(
+        #        qtable,
+        #        sql.replace("''")))
+        else:
+            yield('{0};'.format(sql))
+
+        # Build the insert statement for each row of the current table
+        table_name_ident = table_name.replace('"', '""')
+        res = cu.execute('PRAGMA table_info("{0}")'.format(table_name_ident))
+        column_names = [str(table_info[1]) for table_info in res.fetchall()]
+        q = """SELECT 'INSERT INTO "{0}" VALUES({1})' FROM "{0}";""".format(
+            table_name_ident,
+            ",".join("""'||quote("{0}")||'""".format(col.replace('"', '""')) for col in column_names))
+        query_res = cu.execute(q)
+        for row in query_res:
+            yield("{0};".format(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('{0};'.format(sql))
+
+    yield('COMMIT;')