在PostgreSQL中,你可以使用ALTER TABLE语句来给一个已经存在的表添加主键约束,并指定主键的名字。以下是详细的步骤和SQL语句: 编写SQL语句以添加主键约束: 你需要使用ALTER TABLE语句,并指定要添加主键的列以及主键的名称。以下是一个示例SQL语句: sql ALTER TABLE public.tablename ADD CONSTRAINT pkey_name PRIMARY...
Postgresql has several types of constraints. They are listed below: Primary key constraint Foreign key constraint Unique constraint Check constraint We will add all these constraints with examples in this guide ahead. Syntax ALTER TABLE NAME_OF_TABLE ADD constaint_type (column_name); This is ...
ALTER TABLEADD CONSTRAINT<constraint_name><constraint_definition>; Using ALTER TABLE ADD CONSTRAINT, any of bellow constraints can be added to existing table NOT NULL CHECK UNIQUE PRIMARY KEY FOREIGN KEY Consider that you already have the followingemployeetable. Add UNIQUE Constraint The UNIQUE constra...
PostgreSQL has no option to specify the position of the new column in the table. To add multiple columns to an existing table, you use multiple ADD COLUMN clauses in the ALTER TABLE statement as follows: ALTER TABLE table_name ADD COLUMN column_name1 data_type constraint, ADD COLUMN column...
How to add a NOT NULL constraint to a column in PostgreSQL database with the basic syntax, examples, and points to note when working with NOT NULL constraint.
alter table nop_file_record add constraint PK_nop_file_record primary key (NOP_TENANT_ID, FILE_ID); 2 changes: 1 addition & 1 deletion 2 nop-file/deploy/sql/postgresql/_add_tenant_nop-file.sql Original file line numberDiff line numberDiff line change @@ -1,5 +1,5 @@ alter table...
Statement : ALTER TABLE "public"."flyway_schema_history" ADD CONSTRAINT "flyway_schema_history_pk" PRIMARY KEY ("installed_rank") as of now i have added tablespace in application.properties but it is still trying to ALTER TABLE in defiffrent tablepsace where user does not have access. ...
dialect=postgresql.dialect(), ) 开发者ID:sqlalchemy,项目名称:sqlalchemy,代码行数:26,代码来源:test_compiler.py 示例2: test_exclude_constraint_copy_where_using # 需要导入模块: from sqlalchemy import schema [as 别名]# 或者: from sqlalchemy.schema importAddConstraint[as 别名]deftest_exclude_constr...
| MODIFY { CONSTRAINT constraint_name | PRIMARY KEY | UNIQUE (column [, column ]...) } constraint_state [ CASCADE ] | RENAME CONSTRAINT old_name TO new_name | { drop_constraint_clause }... } out_of_line_constraint: [ CONSTRAINT constraint_name ] ...
column_name data_typeconstraint; 如果要使用单个语句将多个列添加到现有表,请使用以下语法: ALTERTABLEtable_nameADD[COLUMN] column_definition,ADD[COLUMN] column_definition, ...; 不同的数据库系统支持ALTER TABLE ADD COLUMN语句以及一些小的差异。 请在下一节中查看参考资料。