Обсуждение: Query in SQL statement
Am trying to port a mysql statement to postgres.
Please help me in finding the error in this,
CREATE SEQUENCE ai_id;
CREATE TABLE badusers (
id int DEFAULT nextval('ai_id') NOT NULL,
UserName varchar(30),
Date datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
Reason varchar(200),
Admin varchar(30) DEFAULT '-',
PRIMARY KEY (id),
KEY UserName (UserName),
KEY Date (Date)
);
Am always getting foll. Errors,
ERROR: relation "ai_id" already exists
ERROR: syntax error at or near "(" at character 240
Thanks,
Rajesh R
I think this question may be more appropriate for
pgsql-novice@postgresql.org.
Anyrate for the below. Sounds like you maybe already have a table or
sequence called ai_id;
Try doing a DROP SEQUENCE ai_id;
First
Also if you plan to use this sequence only for this table it would be better
to use serial8 which will automatically create the sequence for you. Then
you don't even need that first part. Also you should avoid naming fields
things like Date which tend to be keywords in many kinds of databases.
Try changing your logic to something like
CREATE TABLE badusers (
id serial8,
UserName varchar(30),
Date timestamp DEFAULT now() NOT NULL,
Reason varchar(200),
Admin varchar(30) DEFAULT '-',
PRIMARY KEY (id)
);
CREATE INDEX badusers_username
ON badusers
USING btree
(username);
CREATE INDEX badusers_date
ON badusers
USING btree
(date);
-----Original Message-----
From: R, Rajesh (STSD) [mailto:rajesh.r2@hp.com]
Sent: Thursday, September 29, 2005 9:05 AM
To: pgsql-hackers@postgresql.org; pgsql-performance@postgresql.org
Subject: [HACKERS] Query in SQL statement
Am trying to port a mysql statement to postgres.
Please help me in finding the error in this,
CREATE SEQUENCE ai_id;
CREATE TABLE badusers (
id int DEFAULT nextval('ai_id') NOT NULL,
UserName varchar(30),
Date datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
Reason varchar(200),
Admin varchar(30) DEFAULT '-',
PRIMARY KEY (id),
KEY UserName (UserName),
KEY Date (Date)
);
Am always getting foll. Errors,
ERROR: relation "ai_id" already exists
ERROR: syntax error at or near "(" at character 240
Thanks,
Rajesh R
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> CREATE SEQUENCE ai_id;
> CREATE TABLE badusers (
> id int DEFAULT nextval('ai_id') NOT NULL,
> UserName varchar(30),
> Date datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
> Reason varchar(200),
> Admin varchar(30) DEFAULT '-',
> PRIMARY KEY (id),
> KEY UserName (UserName),
> KEY Date (Date)
> );
>
>
> Am always getting foll. Errors,
>
> ERROR: relation "ai_id" already exists
> ERROR: syntax error at or near "(" at character 240
You have just copied the Mysql code to Postgresql. It will in no way
work. Your default for 'Date' is illegal in postgresql and hence it
must allow NULLs. There is no such thing as a 'datetime' type. There
is no such thing as 'Key'. Also your mixed case identifiers won't be
preserved. You want:
CREATE TABLE badusers (
id SERIAL PRIMARY KEY,
UserName varchar(30),
Date timestamp,
Reason varchar(200),
Admin varchar(30) DEFAULT '-'
);
CREATE INDEX UserName_Idx ON badusers(Username);
CREATE INDEX Date_Idx ON badusers(Date);
On Thu, Sep 29, 2005 at 09:28:38PM +0800, Christopher Kings-Lynne wrote:
>
> >CREATE SEQUENCE ai_id;
> >CREATE TABLE badusers (
> > id int DEFAULT nextval('ai_id') NOT NULL,
> > UserName varchar(30),
> > Date datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
> > Reason varchar(200),
> > Admin varchar(30) DEFAULT '-',
> > PRIMARY KEY (id),
> > KEY UserName (UserName),
> > KEY Date (Date)
> >);
> >
> >
> >Am always getting foll. Errors,
> >
> >ERROR: relation "ai_id" already exists
> >ERROR: syntax error at or near "(" at character 240
>
> You have just copied the Mysql code to Postgresql. It will in no way
> work. Your default for 'Date' is illegal in postgresql and hence it
> must allow NULLs. There is no such thing as a 'datetime' type. There
> is no such thing as 'Key'. Also your mixed case identifiers won't be
> preserved. You want:
>
> CREATE TABLE badusers (
> id SERIAL PRIMARY KEY,
> UserName varchar(30),
> Date timestamp,
> Reason varchar(200),
> Admin varchar(30) DEFAULT '-'
> );
>
> CREATE INDEX UserName_Idx ON badusers(Username);
> CREATE INDEX Date_Idx ON badusers(Date);
Actually, to preserve the case you can wrap everything in quotes:
CREATE ...
"UserName" varchar(30)
Of course that means that now you have to do that in every statement
that uses that field, too...
SELECT username FROM badusers
ERROR
SELECT "UserName" FROM badusers
bad user
I suggest ditching the CamelCase and going with underline_seperators.
I'd also not use the bareword id, instead using bad_user_id. And I'd
name the table bad_user. But that's just me. :)
--
Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
R, Rajesh (STSD) wrote:
>
> Am trying to port a mysql statement to postgres.
>
> Please help me in finding the error in this,
Can I recommend the reference section of the manuals for this sort of
thing? There is an excellent section detailing the valid SQL for the
CREATE TABLE command.
Also - the pgsql-hackers list is for discussion of database development,
and the performance list is for performance problems. This would be
better posted on pgsql-general or -sql or -novice.
> CREATE SEQUENCE ai_id;
This line is causing the first error:
> ERROR: relation "ai_id" already exists
That's because you've already successfully created the sequence, so it
already exists. Either drop it and recreate it, or stop trying to
recreate it.
> CREATE TABLE badusers (
> id int DEFAULT nextval('ai_id') NOT NULL,
> UserName varchar(30),
> Date datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
Well, "Date" is a type-name, "datetime" isn't and even if it was
"0000-00-00" isn't a valid date is it?
> Reason varchar(200),
> Admin varchar(30) DEFAULT '-',
> PRIMARY KEY (id),
> KEY UserName (UserName),
> KEY Date (Date)
The word "KEY" isn't valid here either - are you trying to define an
index? If so, see the "CREATE INDEX" section of the SQL reference.
http://www.postgresql.org/docs/8.0/static/sql-commands.html
If you reply to this message, please remove the pgsql-hackers CC:
--
Richard Huxton
Archonet Ltd