alter

My question is kind of simple. Is it possible to use subqueries within alter expressions in PostgreSQL? I want to alter a sequence value based on a primary key column value. I tried using the following expression, but it wouldn't execute. alter sequence public.sequenceX restart with (select max(table_id)+1 from table) Thanks in advance I don't believe you can do it like that but you should be able to use the setval function direction which is what the alter does. select setval('sequenceX', (select max(table_id)+1 from table), false) The false will make it return the next sequence number as

Don't know if it's possible, I Altered VARCHAR column to Decimal Type which i want to Rollback. Because it blended all floating values as integer. like 2.00 became 200. Is there any way to undo my last table Alteration? Please advise. No, you can't roll back ALTER TABLE statements. https://dev.mysql.com/doc/refman/5.7/en/cannot-roll-back.html Some statements cannot be rolled back. In general, these include data definition language (DDL) statements, such as those that create or drop databases, those that create, drop, or alter tables or stored routines. (emphasis mine) As Chris Peters comments

I have created a view that is based on another view and a table. I want to add new column of type varchar. I did like below, But getting syntax error? I am new to SQL, So,could not understand ALTER VIEW [dbo].[MyView] ADD New_Col varchar(10) null GO you have to write the entire view again and just add or omit what you want to change for example your view is now : create view myView as select field1 from table1 and now you want to add a field called New_Col than you write this : alter view myView as select field1, New_Col from table1 You can't alter a view like a table. You have to script the

Part-time reluctant DBA here. I want to change an existing primary key index from clustered to non-clustered. And the syntax is escaping me. This is how it's scripted out right now. ALTER TABLE [dbo].[Config] WITH NOCHECK ADD CONSTRAINT [PK_Config] PRIMARY KEY CLUSTERED ( [ConfigID] ) ON [PRIMARY] I am not seeing an ALTER CONSTRAINT statement in the online docs. Drop the clustered index, then recreate the primary key as non-clustered: ALTER TABLE dbo.Config DROP CONSTRAINT PK_Config go ALTER TABLE dbo.Config ADD CONSTRAINT PK_Config PRIMARY KEY NONCLUSTERED (ConfigID) 来源： https://stackoverflow

I have an application running with a working table called ANIMAL. Upon first creating this table it consisted simply of _id and animal_name columns. Now I am trying to expand on it, including a animal_biography column, however I am having a little difficulty.At first I thought I was just a case of upgrading my CREATE_TABLE statement to include the animal bio: private static final String DATABASE_CREATE = "create table " + ANIMALS_TABLE + " (_id integer primary key autoincrement, " + "animal_name text not null, " + "biography text not null);"; however, looking at the logcat it tells me the