Create a Sequence with START WITH from Query
How can I create a Sequence where m开发者_C百科y START WITH value comes from a query?
I'm trying this way:
CREATE SEQUENCE "Seq" INCREMENT BY 1 START WITH (SELECT MAX("ID") FROM "Table");
But, I get the ORA-01722 error
The START WITH CLAUSE accepts an integer. You can form the "Create sequence " statement dynamically and then execute it using execute immediate to achieve this.
declare
l_new_seq INTEGER;
begin
select max(id) + 1
into l_new_seq
from test_table;
execute immediate 'Create sequence test_seq_2
start with ' || l_new_seq ||
' increment by 1';
end;
/
Check out these links.
http://download.oracle.com/docs/cd/B14117_01/server.101/b10759/statements_6014.htm
http://download.oracle.com/docs/cd/B19306_01/appdev.102/b14261/executeimmediate_statement.htm
Here I have my example which works just fine:
declare
ex number;
begin
select MAX(MAX_FK_ID) + 1 into ex from TABLE;
If ex > 0 then
begin
execute immediate 'DROP SEQUENCE SQ_NAME';
exception when others then
null;
end;
execute immediate 'CREATE SEQUENCE SQ_NAME INCREMENT BY 1 START WITH ' || ex || ' NOCYCLE CACHE 20 NOORDER';
end if;
end;
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