Re: Initializing a new record where field is NULL by default
On 31. jan. 2015, at 20.22, Bob M rgmatth...@orcon.net.nz wrote: Hi Dyre I am still not grasping this. I have psInsert = conn.prepareStatement(INSERT INTO TABLE VALUES(?, ?.., ?) [27 of them] psInsert.setString(1, date); psInsert.setString(25, class); psInsert.setString(26, Trade_ID); but I am unclear what to put for the final line referring to Profit and where I wish to set it to NULL initially which is the default There are two different strategies here: 1) Just insert an SQL NULL manually: psinsert.setNull(number, java.sql.Types.DOUBLE); // See javadoc for PreparedStatement or, psinsert.setNull(“PROFIT_LOSS”, java.sql.Types.DOUBLE) 2) Change the definition of the table: CREATE TABLE T(….., PROFIT_LOSS DOUBLE DEFAULT NULL, …) then when inserting INSERT INTO T(col1, col2, …, col after PROFIT_LOSS, more columns,…) VALUES (?,?,… ?) You have to spell out the columns you are inserting into, unless the columns with default values are the last columns in the table. In that case you can just omit them in the insert Bob M -- View this message in context: http://apache-database.10148.n7.nabble.com/Initializing-a-new-record-where-field-is-NULL-by-default-tp143732p143735.html Sent from the Apache Derby Users mailing list archive at Nabble.com.
Re: Initializing a new record where field is NULL by default
You have to spell out the columns you are inserting into, unless the columns with default values are the last columns in the table. In that case you can just omit them in the insert I'm pretty sure it's a bit more flexible than that. I believe that if you don't say NOT NULL, and you don't have a DEFAULT clause, then DEFAULT NULL is automatic. And I believe you can name the columns in any order (so long as they line up with the VALUES values), so they don't have to be the last columns in the table. So you can INSERT INTO T (c, f, a, g, b ) VALUES ( .. ) and columns d and e and h will get NULL values since they weren't mentioned in the insert. thanks, bryan
Re: Initializing a new record where field is NULL by default
Thank's Bryan for that information... I have sorted it out now The profit field is a dec(5,2) field and so I am using DEFAULT 999.99 Then when I wish to update the latest record with the profit I use a WHERE profit=999.99 All good :) Thanks Bob M -- View this message in context: http://apache-database.10148.n7.nabble.com/Initializing-a-new-record-where-field-is-NULL-by-default-tp143732p143738.html Sent from the Apache Derby Users mailing list archive at Nabble.com.
Re: Initializing a new record where field is NULL by default
On 02/01/2015 05:42 PM, Bryan Pendleton wrote: You have to spell out the columns you are inserting into, unless the columns with default values are the last columns in the table. In that case you can just omit them in the insert I'm pretty sure it's a bit more flexible than that. I believe that if you don't say NOT NULL, and you don't have a DEFAULT clause, then DEFAULT NULL is automatic. And I believe you can name the columns in any order (so long as they line up with the VALUES values), so they don't have to be the last columns in the table. So you can INSERT INTO T (c, f, a, g, b ) VALUES ( .. ) and columns d and e and h will get NULL values since they weren't mentioned in the insert. That is indeed much more convenient. Thanks for pointing that out :) -- Regards, Dyre
