id summary reporter owner description type status component version severity resolution keywords cc stage has_patch needs_docs needs_tests needs_better_patch easy ui_ux 27151 FK index created two times on PostgreSQL if referenced table PK is varchar Kamil Kujawiński nobody "Django version: 1.8.14 '''Scenario 1. with creating index only''' 1. Initial models: {{{ class Foo(models.Model): guid = models.CharField(max_length=36, primary_key=True) class Bar(models.Model): key = models.ForeignKey(Foo, db_index=False) }}} 2. Initial migration: {{{ class Migration(migrations.Migration): dependencies = [] operations = [ migrations.CreateModel( name='Bar', fields=[ ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)), ], ), migrations.CreateModel( name='Foo', fields=[ ('guid', models.CharField(max_length=36, serialize=False, primary_key=True)), ], ), migrations.AddField( model_name='bar', name='key', field=models.ForeignKey(to='myapp.Foo', db_index=False), ), ] }}} 3. Changes in to model: {{{ - key = models.ForeignKey(Foo, db_index=False) + key = models.ForeignKey(Foo, db_index=True) }}} 4. Migration: {{{ class Migration(migrations.Migration): dependencies = [ ('myapp', '0001_initial'), ] operations = [ migrations.AlterField( model_name='bar', name='key', field=models.ForeignKey(to='myapp.Foo'), ), ] }}} 5. Applying migration logs: {{{ Operations to perform: Apply all migrations: myapp Running migrations: Rendering model states... DONE Applying myapp.0002_auto_20160829_1936...[2016-08-29 19:37:55,385 pid=11084] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" DROP CONSTRAINT ""myapp_bar_key_id_1647a22de55ad985_fk_myapp_foo_id""; (params []) [2016-08-30 11:26:19,228 pid=25347] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" DROP CONSTRAINT ""myapp_bar_key_id_1647a22de55ad985_fk_myapp_foo_guid""; (params []) [2016-08-30 11:26:19,230 pid=25347] DEBUG | django.db.backends.schema | CREATE INDEX ""myapp_bar_key_id_1647a22de55ad985_uniq"" ON ""myapp_bar"" (""key_id""); (params []) [2016-08-30 11:26:19,230 pid=25347] DEBUG | django.db.backends.schema | CREATE INDEX ""myapp_bar_key_id_1647a22de55ad985_uniq"" ON ""myapp_bar"" (""key_id""); (params []) [2016-08-30 11:26:19,235 pid=25347] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" ADD CONSTRAINT ""myapp_bar_key_id_1647a22de55ad985_fk_myapp_foo_guid"" FOREIGN KEY (""key_id"") REFERENCES ""myapp_foo"" (""guid"") DEFERRABLE INITIALLY DEFERRED; (params []) [2016-08-30 11:26:19,235 pid=25347] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" ADD CONSTRAINT ""myapp_bar_key_id_1647a22de55ad985_fk_myapp_foo_guid"" FOREIGN KEY (""key_id"") REFERENCES ""myapp_foo"" (""guid"") DEFERRABLE INITIALLY DEFERRED; (params []) [2016-08-30 11:26:19,237 pid=25347] DEBUG | django.db.backends.schema | CREATE INDEX ""myapp_bar_key_id_1647a22de55ad985_like"" ON ""myapp_bar"" (""key_id"" varchar_pattern_ops); (params []) [2016-08-30 11:26:19,237 pid=25347] DEBUG | django.db.backends.schema | CREATE INDEX ""myapp_bar_key_id_1647a22de55ad985_like"" ON ""myapp_bar"" (""key_id"" varchar_pattern_ops); (params []) OK }}} 6. Indexes created in postgres database {{{ SELECT i.relname as indname, i.relowner as indowner, idx.indrelid::regclass, am.amname as indam, idx.indkey, ARRAY(SELECT pg_get_indexdef(idx.indexrelid, k + 1, true) FROM generate_subscripts(idx.indkey, 1) as k ORDER BY k) as indkey_names, idx.indexprs IS NOT NULL as indexprs, idx.indpred IS NOT NULL as indpred, idx.indisunique FROM pg_index as idx JOIN pg_class as i ON i.oid = idx.indexrelid JOIN pg_am as am ON i.relam = am.oid WHERE idx.indrelid::regclass='myapp_bar'::regclass; indname | indowner | indrelid | indam | indkey | indkey_names | indexprs | indpred | indisunique ----------------------------------------+----------+-----------+-------+--------+--------------+----------+---------+------------- myapp_bar_key_id_1647a22de55ad985_like | 16384 | myapp_bar | btree | 2 | {key_id} | f | f | f myapp_bar_key_id_1647a22de55ad985_uniq | 16384 | myapp_bar | btree | 2 | {key_id} | f | f | f myapp_bar_pkey | 16384 | myapp_bar | btree | 1 | {id} | f | f | t }}} '''Scenario 2. indexes created in first migration''' 1. Initial models: {{{ class Foo(models.Model): guid = models.CharField(max_length=36, primary_key=True) class Bar(models.Model): key = models.ForeignKey(Foo, db_index=True) }}} 2. Initial migration: {{{ class Migration(migrations.Migration): dependencies = [ ('myapp', '0033_auto_20160829_1931'), ] operations = [ migrations.CreateModel( name='Bar', fields=[ ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)), ], ), migrations.CreateModel( name='Foo', fields=[ ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)), ], ), migrations.AddField( model_name='bar', name='key', field=models.ForeignKey(to='myapp.Foo'), ), ] }}} 3. Applying migration logs: {{{ Operations to perform: Apply all migrations: myapp Running migrations: Rendering model states... DONE Applying myapp.0034_auto_20160830_1136...[2016-08-30 11:37:00,682 pid=28406] DEBUG | django.db.backends.schema | CREATE TABLE ""myapp_bar"" (""id"" serial NOT NULL PRIMARY KEY); (params None) [2016-08-30 11:37:00,682 pid=28406] DEBUG | django.db.backends.schema | CREATE TABLE ""myapp_bar"" (""id"" serial NOT NULL PRIMARY KEY); (params None) [2016-08-30 11:37:00,704 pid=28406] DEBUG | django.db.backends.schema | CREATE TABLE ""myapp_foo"" (""id"" serial NOT NULL PRIMARY KEY); (params None) [2016-08-30 11:37:00,704 pid=28406] DEBUG | django.db.backends.schema | CREATE TABLE ""myapp_foo"" (""id"" serial NOT NULL PRIMARY KEY); (params None) [2016-08-30 11:37:00,749 pid=28406] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" ADD COLUMN ""key_id"" integer NOT NULL; (params []) [2016-08-30 11:37:00,749 pid=28406] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" ADD COLUMN ""key_id"" integer NOT NULL; (params []) [2016-08-30 11:37:00,750 pid=28406] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" ALTER COLUMN ""key_id"" DROP DEFAULT; (params []) [2016-08-30 11:37:00,750 pid=28406] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" ALTER COLUMN ""key_id"" DROP DEFAULT; (params []) [2016-08-30 11:37:00,751 pid=28406] DEBUG | django.db.backends.schema | CREATE INDEX ""myapp_bar_30f69126"" ON ""myapp_bar"" (""key_id""); (params []) [2016-08-30 11:37:00,751 pid=28406] DEBUG | django.db.backends.schema | CREATE INDEX ""myapp_bar_30f69126"" ON ""myapp_bar"" (""key_id""); (params []) [2016-08-30 11:37:00,759 pid=28406] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" ADD CONSTRAINT ""myapp_bar_key_id_1647a22de55ad985_fk_myapp_foo_id"" FOREIGN KEY (""key_id"") REFERENCES ""myapp_foo"" (""id"") DEFERRABLE INITIALLY DEFERRED; (params []) [2016-08-30 11:37:00,759 pid=28406] DEBUG | django.db.backends.schema | ALTER TABLE ""myapp_bar"" ADD CONSTRAINT ""myapp_bar_key_id_1647a22de55ad985_fk_myapp_foo_id"" FOREIGN KEY (""key_id"") REFERENCES ""myapp_foo"" (""id"") DEFERRABLE INITIALLY DEFERRED; (params []) OK }}} 4. Indexes created in postgres database {{{ SELECT i.relname as indname, i.relowner as indowner, idx.indrelid::regclass, am.amname as indam, idx.indkey, ARRAY(SELECT pg_get_indexdef(idx.indexrelid, k + 1, true) FROM generate_subscripts(idx.indkey, 1) as k ORDER BY k) as indkey_names, idx.indexprs IS NOT NULL as indexprs, idx.indpred IS NOT NULL as indpred, idx.indisunique FROM pg_index as idx JOIN pg_class as i ON i.oid = idx.indexrelid JOIN pg_am as am ON i.relam = am.oid WHERE idx.indrelid::regclass='myapp_bar'::regclass; indname | indowner | indrelid | indam | indkey | indkey_names | indexprs | indpred | indisunique ----------------------------------------+----------+-----------+-------+--------+--------------+----------+---------+------------- myapp_bar_30f69126 | 16384 | myapp_bar | btree | 2 | {key_id} | f | f | f myapp_bar_key_id_1647a22de55ad985_like | 16384 | myapp_bar | btree | 2 | {key_id} | f | f | f myapp_bar_pkey | 16384 | myapp_bar | btree | 1 | {id} | f | f | t (3 rows) }}} Note: I've edited manually in logs app name and migration numbers. I hope it didn't intefere this test case. " Bug closed Migrations 1.8 Normal invalid Accepted 0 0 0 0 0 0