country_id | character varying(2) | not null Indexes:"locations_pkey" PRIMARY KEY, btree (location_id, country_id) Now execute the following statement. Sample Solution: Code: ALTERTABLElocationsDROPCONSTRAINTlocations_pkey; Copy Output: Now see the structure of the table locations after alteration...
PostgreSQL: 在PostgreSQL中,你可以通过 ALTER TABLE 命令来删除主键或唯一约束。 sql -- 假设要删除主键约束的表名为 `my_table` ALTER TABLE my_table DROP CONSTRAINT my_primary_key_constraint; -- 假设要删除唯一约束的表名为 `my_table`,约束名为 `unique_constraint_name` ALTER TABLE my_table DROP...
CREATETABLE`ddl`(`id`int(10)unsignedNOTNULLAUTO_INCREMENT,`c1`int(10)NOTNULLDEFAULT'0',`c2`int(10)unsignedNOTNULLDEFAULT'0',`c3`timestampNOTNULLDEFAULTCURRENT_TIMESTAMPONUPDATECURRENT_TIMESTAMP,PRIMARYKEY(`id`),UNIQUEKEY`c2`(`c2`),KEY`idx_c1`(`c1`))ENGINE=InnoDBAUTO_INCREMENT=20000001DEF...
CREATE TABLE orders (order_id int PRIMARY KEY, order_date date,…); CREATE TABLE items (order_id int REFERENCES orders, quantity int,…); 根据您的删除行为,PolarDB PostgreSQL版(兼容Oracle)在删除orders表时执行以下操作: 如果您指定 DROP TABLE orders RESTRICT,PolarDB PostgreSQL版(兼容Oracle)将报告错...
I renamed a primary key and runs into the foreign key constraint: migrations.RenameField( model_name='itemtype', old_name='item_id', new_name='item_type_id', ), Output: django.db.utils.InternalError: cannot drop constraint dpe_itemtype_pkey on table dpe_itemtype because other objects...
在java.time.LocalDateTime上映射postgresql类型‘时间戳带时区’时,我遇到了问题。我使用的是: postgresql,带有hibernate的下拉向导。 表: 代码语言:javascript 运行 AI代码解释 CREATE SEQUENCE "auth"."roles_seq_id"; CREATE TABLE "auth"."roles" ( id BIGINT NOT NULL DEFAULT nextval('auth.roles_seq_id'...
CREATE[TEMPORARY|TEMP]TABLEtable(columntype [NULL|NOTNULL] [UNIQUE] [DEFAULTvalue ] [column_constraint_clause |PRIMARYKEY} [ ... ] ] [, ... ] [,PRIMARYKEY(column[, ...] ) ] [,CHECK( condition ) ] [, table_constraint_clause ] ) [ INHERITS ( inherited_table [, ...] ) ]TEMPOR...
2) Drop a column that is referenced by a constraint First, attempt to remove the publisher_id column from the books table: ALTER TABLE books DROP COLUMN publisher_id; PostgreSQL issued the following error: ERROR: cannot drop table books column publisher_id because other objects depend on it ...
DROP TABLE IF EXISTS purcchase_orders;Code language: PostgreSQL SQL dialect and PL/pgSQL (pgsql) Dropping tables with constraints First, create two new tables called brands and cars: CREATE TABLE brands ( brand_id NUMBER PRIMARY KEY, brand_name varchar2 (50) ); CREATE TABLE cars ( car_...
I have an erroneous unique_together constraint on a model's primary key (unique_together = (('id',),)) that cannot be dropped by a migration. Apparently the migration tries to find all unique constraints on the column and expects there to be only one, but I've got two — the primary...