I'm trying to use peewee's migration module to rename a column from name to title in my page table. However I'm running this confusing error:
peewee.OperationalError: table page__tmp__ has no column named FOREIGN
My guess is that it has something to do with the need to create an intermediary table when using sqlite.
Current Model:
Full source is here https://github.com/csytan/textmug/blob/master/db.py
class User(BaseModel):
id = peewee.CharField(primary_key=True, max_length=20)
class Page(BaseModel):
id = peewee.PrimaryKeyField()
name = peewee.TextField(unique=True, null=True)
user = peewee.ForeignKeyField(User, null=True, related_name='pages')
Migration Script:
from playhouse import migrate
my_db = migrate.SqliteDatabase('database')
migrator = migrate.SqliteMigrator(my_db)
with my_db.transaction():
migrate.migrate(
migrator.rename_column('page', 'name', 'title')
)
I ended up doing it manually with the sqlite3 command line tool:
BEGIN;
ALTER TABLE "page" RENAME TO "page_tmp";
CREATE TABLE "page" ("id" INTEGER NOT NULL PRIMARY KEY, "title" TEXT, "user_id" TEXT, "created" DATETIME NOT NULL, "text" TEXT NOT NULL, "public" SMALLINT NOT NULL, "encrypted" SMALLINT NOT NULL, FOREIGN KEY ("user_id") REFERENCES "user" ("id"));
INSERT INTO "page" SELECT "id","name","user_id","created","text","public","encrypted" FROM "page_tmp";
DROP TABLE "page_tmp";
COMMIT;
Related
I am using SQLite and DB Browser for SQLite. I know that if you want to insert a foreign key using the GUI, you just have to scroll to the right and double click to insert the foreign key to the corresponding field. The problem is when you want to use a multiple foreign key. How or where should i put the multiple foreign key constrain using the GUI ?
my actual sql is (returns an exception 'foreign key mismatch - "diseases" referencing "beehives"...'):
CREATE TABLE "diseases" (
"id" INTEGER NOT NULL,
"id_beehive" INTEGER NOT NULL,
"id_apiary" INTEGER NOT NULL,
"disease" TEXT NOT NULL,
"treatment" TEXT NOT NULL,
"start_treat_date" DATE NOT NULL,
"end_treat_date" DATE,
PRIMARY KEY("id"),
FOREIGN KEY("id_beehive") REFERENCES "beehives"("number") ON UPDATE CASCADE,
FOREIGN KEY("id_apiary") REFERENCES "beehives"("id_apiary") ON UPDATE CASCADE
);
what i want to do using the gui is:
CREATE TABLE "diseases" (
"id" INTEGER NOT NULL,
"id_beehive" INTEGER NOT NULL,
"id_apiary" INTEGER NOT NULL,
"disease" TEXT NOT NULL,
"treatment" TEXT NOT NULL,
"start_treat_date" DATE NOT NULL,
"end_treat_date" DATE,
PRIMARY KEY("id"),
FOREIGN KEY("id_beehive","id_apiary") REFERENCES "beehives"("number","id_apiary") ON UPDATE CASCADE
);
beehives sql:
CREATE TABLE "beehives" (
"number" INTEGER NOT NULL,
"id_apiary" INTEGER NOT NULL DEFAULT -2,
"date" DATE,
"type" TEXT,
"favorite" BOOLEAN DEFAULT 'false',
PRIMARY KEY("number","id_apiary"),
FOREIGN KEY("id_apiary") REFERENCES "apiaries"("id") ON DELETE SET NULL
);
After researching, it is not possible for the moment.
Everytime you modify the structure of the table, what DB Browser for SQLite do on the background is renaming the table, creating a new table with the updated structure, move the data to this new table and delete the old table. So in the GUI it looks like its only updating.
Unfortunatly, to create a composite foreign key or modify a simple FK to a composite FK , you can only do it manualy from the SQL window.
example :
FOREIGN KEY("id_beehive","id_apiary") REFERENCES "beehives"("number","id_apiary") ON
UPDATE CASCADE
According to the SQLite documentation / FAQ a column declared INTEGER PRIMARY KEY will automatically get a value of +1 the highest of the column if omitted.
Using SQLite version 3.22.0 2018-01-22 18:45:57
Creating a table as follows:
CREATE TABLE test (
demo_id INTEGER PRIMARY KEY NOT NULL,
ttt VARCHAR(40) NOT NULL,
basic VARCHAR(25) NOT NULL,
name VARCHAR(255) NOT NULL,
UNIQUE(ttt, basic) ON CONFLICT ROLLBACK
) WITHOUT ROWID;
Then inserting like this:
INSERT INTO test (ttt, basic, name) VALUES ('foo', 'bar', 'This is
a test');
gives:
Error: NOT NULL constraint failed: test.demo_id
sqlite>
When it is expected to create a record with a demo_id value of 1. Even if the table already contains values, it'll fail inserting the row without explicitly specifying the id with the same error.
What am I doing wrong?
The documentation says that you get autoincrementing values for the rowid. But you specified WITHOUT ROWID.
I am trying to convert the table that was dumped from mysql. Following is the code I have from mysql for creating the table:
CREATE TABLE "tbl_profession_attributes" (
"id" bigint(20) NOT NULL,
"tbl_profession_attribute_id" bigint(20) DEFAULT '0',
"code" varchar(10) NOT NULL,
"name" varchar(100) NOT NULL,
"keyword" text NOT NULL,
"tbl_profession_list_id" bigint(20) NOT NULL,
PRIMARY KEY ("id"),
KEY "tbl_passion_attribute_id" ("tbl_profession_attribute_id"),
KEY "tbl_passion_list_id" ("tbl_profession_list_id")
);
When I run this query for sqlite, I get the following error:
Query Error: near "KEY": syntax error Unable to execute statement
Can someone please help me resolve this.
Any help is much appreciated.
First, MySQL keyword KEY is synonym for INDEX. So this is not about foreign key at all.
Second, SQLite does not support creating non-primary index in CREATE TABLE statement. You should specify separate statement for create index, something like:
CREATE INDEX tbl_passion_attribute_id_idx
ON tbl_profession_attributes(tbl_profession_attribute_id)
I have two tables auth_user and temp
These are their schema:
CREATE TABLE "auth_user" (
"id" integer NOT NULL PRIMARY KEY,
"username" varchar(30) NOT NULL UNIQUE,
"first_name" varchar(30) NOT NULL,
"last_name" varchar(30) NOT NULL,
"email" varchar(75) NOT NULL,
"password" varchar(128) NOT NULL,
"is_staff" bool NOT NULL,
"is_active" bool NOT NULL,
"is_superuser" bool NOT NULL,
"last_login" datetime NOT NULL,
"date_joined" datetime NOT NULL
);
CREATE TABLE "temp" ( "id" integer, "username" varchar(30));
I want the id fields in the auth_user table to be updated to the id field of the temp table provided the username is the same. How can I achieve this?
I tried this SQL:
Update auth_user set id=(select temp.id from temp where temp.username=auth_user.username);
But I get this error:
Error: datatype mismatch
I found this question Update table values from another table with the same user name
It is similar to my question. Looking at the answer in that page, I tried this query
update auth_user set id=(select temp.id from temp where temp.username=auth_user.username) where exists (select * from temp where temp.username=auth_user.username);
and it works great. Same as my query in the question but with just an extra where clause. I don't get the Error: datatype mismatch now (but I don't know the exact reason why).
I have created one table in oracle data base my table script is
CREATE TABLE wsc_widget_bundle (
id VARCHAR (50),
widgetBundle BLOB NULL,
devicesoftwareclass VARCHAR(30) NOT NULL,
widgetProfileId VARCHAR (50) NOT NULL,
bundleHash BLOB NULL,
widgetLocale VARCHAR (6) NOT NULL ,
status INT,
primary key(id),
unique(widgetProfileId, devicesoftwareclass,status),
foreign key(widgetProfileId) references wsc_widget_profile(id)
);
When i create ddl for that is looks like
create table "DEV1"."WSC_WIDGET_BUNDLE"(
"ID" VARCHAR2(50) not null,
"WIDGETBUNDLE" BLOB,
"DEVICESOFTWARECLASS" VARCHAR2(30) not null,
"WIDGETPROFILEID" VARCHAR2(50) not null,
"BUNDLEHASH" BLOB,
"WIDGETLOCALE" VARCHAR2(6) not null,
"STATUS" NUMBER,
constraint "SYS_C00323290" primary key ("ID")
);
alter table "DEV1"."WSC_WIDGET_BUNDLE"
add constraint "SYS_C00323292"
foreign key ("WIDGETPROFILEID")
references "MTP440_DEV1"."WSC_WIDGET_PROFILE"("ID");
create unique index "MTP440_DEV1"."SYS_C00323290" on "MTP440_DEV1"."WSC_WIDGET_BUNDLE"("ID");
create unique index "MTP440_DEV1"."SYS_C00323291" on "MTP440_DEV1"."WSC_WIDGET_BUNDLE"("WIDGETPROFILEID","DEVICESOFTWARECLASS","STATUS");
create index "MTP440_DEV1"."TEST" on "MTP440_DEV1"."WSC_WIDGET_BUNDLE"("DEVICESOFTWARECLASS","STATUS","WIDGETLOCALE","WIDGETPROFILEID");
Now i want to write alter script to alter unique key constrain of my table but as at creation of table I didn't mention the name of my unique key name it is given by system like SYS_C00323291
So how can I write alter script to drop that unique key whose name is not known to me and generation new one
You can find the name of the constraint by querying the user_constraints and user_cons_columns views.
Alter table x
drop constraint pk;
Alter table x
add constraint New_constraint_name PRIMARY KEY (colname);