Hi :) Can you right-click on a relationship's join-line and edit it's properties? Shouldn't the relationships be part of the back-end rather than defined in the front-end? Regards from Tom :)
>________________________________ > From: Dan Lewis <[email protected]> >To: [email protected] >Sent: Wednesday, 9 January 2013, 4:14 >Subject: Re: [libreoffice-users] Re: Base scenario > >Comment inline below. > >--Dan > >On 01/08/2013 07:07 PM, Girvin R. Herr wrote: >> Ian, >> Have you actually drawn any relationships? Base will not do that for you. >> Just adding the tables in the 'Relationships Window' will not create the >> relationships automagically. You must click and hold on the one table >> element (remote key) and drag over to the related table's element (primary >> key), then release the mouse button. Base will then draw a line between the >> two. Note, the order of the drag is important. It determines the type of >> join. Joins are confusing to me too, so I can't help much there. I had to >> experiment with the direction to get it to work right. I think it was >> remote key to primary key, but I am not sure of that any more. >> >> Warning! The way the SQL language is set up, if either of the ends of a >> join (relationship) is NULL, then the record will be discarded and not show >> up in your result set. No warnings, no errors. Data records will just be >> missing. IMHO, this is stupid (my mantra is: "thou shall not lose data"), >> but that is how the SQL language was set up. So, make sure any joined data >> elements in all of your table records are not NULL. Note that NULL is not >> zero (0) and vice-versa! NULL means that there is no data in the record >> element. I use a lot of remote keys in my database main tables that point >> to primary keys (options) in other tables. In those other tables, I have >> made it a point to make the data elements of the first record to be "-", >> which is my equivalent of unknown, just to have something to select that is >> not NULL. You could probably use a blank (" "), but I prefer seeing the "-" >> in forms and reports. Most times in reports, it is hard to see anyway. Seeing the "-" tells me the field is not NULL. >> Hope this helps. >> Girvin Herr >> > These statements about joins do not seem to be quite correct. What you >are describing is an Inner Join: you will only see the rows of data in which >both the foreign (remote) key and the primary key have a value. > Suppose we have two tables A and B and that the foreign (remote) key is >in table A and the primary key is in table B. > Example 1: table A Left Outer Join table B. The output (result set) for >this contains all the fields in table A and their values on the left side of >the combined table. The right side contains all the fields in Table B. The >rows in which the primary key value matches the foreign key value, data from >both table appear in the output. However, where there is no primary key value >in table B that matches the foreign key value in table A, all the fields from >table B for that row will be NULL. > Example 2: table A Right Outer Join table B. The output for this contains >all the fields in table B and their values on the right side. For each output >row in which the foreign key does not have a value that matches any value of >the primary key, the fields in the left side of it will be NULL. > Example 3: table A Cross Join table B. This is also referred to as a >Cartesian Product. In this case, each row of table A is joined to all the rows >of table B. This contains all of the possible combinations of combining both >tables. Usually, some rows of the output will have the table A fields all >showing NULL while others will have the fields of table B showing all NULL. > >> >> Ian Whitfield wrote: >>> Hi All >>> >>> Re - My previous post.... Have been doing some Googling etc and found the >>> 'Relationships Window' for setting Relationships. >>> >>> I can get the Window up, select my Tables but it _DOES NOT_ draw any >>> connecting lines or set any Relationships!!?? >>> >>> Is this another "Gotcha" of using MySQL and Base together? As it does _NOT_ >>> seem to work at all!! >>> >>> I'm using PCLinuxOS 2012, LO Base 3.6.2.2 and MySQL 5.1.55 >>> >>> IanW >>> Pretoria RSA. >>> >> > > >-- For unsubscribe instructions e-mail to: [email protected] >Problems? http://www.libreoffice.org/get-help/mailing-lists/how-to-unsubscribe/ >Posting guidelines + more: http://wiki.documentfoundation.org/Netiquette >List archive: http://listarchives.libreoffice.org/global/users/ >All messages sent to this list will be publicly archived and cannot be deleted > > > > -- For unsubscribe instructions e-mail to: [email protected] Problems? http://www.libreoffice.org/get-help/mailing-lists/how-to-unsubscribe/ Posting guidelines + more: http://wiki.documentfoundation.org/Netiquette List archive: http://listarchives.libreoffice.org/global/users/ All messages sent to this list will be publicly archived and cannot be deleted
