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From "Jean T. Anderson" <...@bristowhill.com>
Subject Suggestions for Derby description on DdlUtils web site
Date Sat, 26 Nov 2005 20:47:18 GMT
Greetings, all,

Here are a couple corrections/suggestions for the Derby info on this page:

http://db.apache.org/ddlutils/database-support.html#Cloudscape%2FDerby

(1) A picky comment regarding this (feel free to ignore):

  "The Apache Derby project is based upon Cloudscape."

Actually, Cloudscape is based on Apache Derby.

Longer explanation: Apache Derby started off with a copy of the 
Cloudscape source code; but, moving forward, Cloudscape is based on the 
Apache Derby codeline.

(2) "The SQL syntax and datatypes supported by Derby are described in 
the Datatypes section in the Reference Manual". The link for the 
Reference Manual is broken:

http://incubator.apache.org/derby/manuals/reference/sqlj02.html#Reference+Manual

Either of these will get you to the Reference Manual (the first would 
allow accessing the Reference Manual for any release):

    http://db.apache.org/derby/manuals/index.html
    http://db.apache.org/derby/docs/dev/ref/

(3) "NULL is explicitly specified as default value" -- currently set to 
"no".

Maybe I'm misunderstanding what is meant.  You can explicitly specify a 
default of NULL:

ij> create table foo (bar int default NULL);
0 rows inserted/updated/deleted


(4) "Foreign key definitions embedded in table definition" -- currently 
set to "no", but Derby does support this. Here's an example from 
http://db.apache.org/derby/docs/dev/ref/rrefsqlj13590.html :

CREATE TABLE FLTAVAIL
	(
	FLIGHT_ID CHAR(6) NOT NULL,
	SEGMENT_NUMBER INT NOT NULL,
	FLIGHT_DATE DATE NOT NULL,
	ECONOMY_SEATS_TAKEN INT,
	BUSINESS_SEATS_TAKEN INT,
	FIRSTCLASS_SEATS_TAKEN INT,
	CONSTRAINT FLTAVAIL_PK PRIMARY KEY (FLIGHT_ID, SEGMENT_NUMBER),
	CONSTRAINT FLTS_FK
	FOREIGN KEY (FLIGHT_ID, SEGMENT_NUMBER)
	REFERENCES Flights (FLIGHT_ID, SEGMENT_NUMBER);

cheers,

  -jean


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