x/sqlalchemy-migrate
Code Issues Proposed changes

Use legacy_alter_table ON in sqlite recreate_table

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Use "PRAGMA legacy_alter_table = ON" with sqlite >= 3.26 when
using "ALTER TABLE RENAME TO migration_tmp" to maintain legacy
behavior.

As of sqlite version 3.26, when a table is renamed using
"ALTER TABLE RENAME TO", REFERENCES clauses that refer to the
table will be updated. To maintain legacy (3.24 and earlier)
behavior, "PRAGMA legacy_alter_table" can be set to true and
"PRAGMA foreign_keys" can be set to false. [1]

[1] https://www.sqlite.org/src/info/ae9638e9c0ad0c36

Thanks to "László Böszörményi (GCS)" <gcs@debian.org> for
providing the code for this patch, which has since been
slightly modified.

Change-Id: I539988ab2ad6df6c8f423ecec15364ad8fcc7267
Closes-Bug: 1807262
This commit is contained in:
Corey Bryant 2018-12-07 13:49:20 -05:00 committed by Matt Riedemann
parent 8fd7226f18
commit 231a4d2ae9
1 changed files with 9 additions and 0 deletions
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9
migrate/changeset/databases/sqlite.py
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@ -96,8 +96,17 @@ class SQLiteHelper(SQLiteCommon):
if omit_constraints is None or cons.name not in omit_constraints
])
# Use "PRAGMA legacy_alter_table = ON" with sqlite >= 3.26 when
# using "ALTER TABLE RENAME TO migration_tmp" to maintain legacy
# behavior. See: https://www.sqlite.org/src/info/ae9638e9c0ad0c36
if self.connection.engine.dialect.server_version_info >= (3, 26):
self.append('PRAGMA legacy_alter_table = ON')
self.execute()
self.append('ALTER TABLE %s RENAME TO migration_tmp' % table_name)
self.execute()
if self.connection.engine.dialect.server_version_info >= (3, 26):
self.append('PRAGMA legacy_alter_table = OFF')
self.execute()
insertion_string = self._modify_table(table, column, delta)