Simple join question
Hi guys, I'm confused.I was always told that one table can have ONLY 1 primary key. is this true or false? Or a table can cause several primary keys?
Second question is, if I join two tables that are formed as a result of columns.
Table 1:
Account_number
Account_create_month
Customer_address
Table 2:
Account_number
Account_create_month
Customer_phone
Should I join on account_number AND account_create_month? If yes why? and why not? Sorry if this is a stupid question. I'm just very confused. Thank you
Hello
Z KHAN wrote:
Hi guys, I'm confused.I was always told that one table can have ONLY 1 primary key. is this true or false? Or a table can cause several primary keys?
A table can have 1 primary key. There may be any number of columns (1, 2, 3 or more) in the primary key.
A table can contain any number of unique keys.
Second question is, if I join two tables that are formed as a result of columns.
Table 1:
Account_number
Account_create_month
Customer_addressTable 2:
Account_number
Account_create_month
Customer_phoneShould I join on account_number AND account_create_month? If yes why? and why not? Sorry if this is a stupid question. I'm just very confused. Thank you
No, you do not have to connect using the two. If you use the two in a join given or not depends on what the data means, and what results you want.
Tags: Database
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Select rgl.trxn_date, rgl.subinventory
rgl.line_count gross_line_count
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of SCO_REQGROSSLINES_V vo
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Okay, so you have these lines containing data from vo but NULL values, where the rlc data was supposed to go. Now it's time to start the WHERE clause. You then apply that conditions in the WHERE clause:AND rlc.trxn_date BETWEEN ...
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All the columns in involivn conditions of rlc probably needs to be part of the join condition, not the WHERE clause.
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Always use (at least) two arguments when calling TO_DATE.
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It is no difference between tables and views (or subqueries) in this regard: the same thing would happen, whether it is vo and rlc really tables or not.
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RahulMac_Freak_Rahul wrote:
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What's not here?
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I want to have commands like update
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Whenever you have a problem, please post a small example data (CREATE TABLE and only relevant columns, INSERT statements), so that people who want to help you can recreate the problem and test their ideas.
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2843667 wrote:
What's not here?
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I want to have commands like update
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Select "update lookup_Nationalities set NAME =" Philippinien "where NAME =' |" NAME
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Al
achunekeThe server has a built-in SATA controller? The manual says 6 SATA connectors, but when I tried to configure the server for the purchase, it was persistent to choose me a PERC controller card. If there is a controller of the motherboard, will it be enough?Yes, he does. Don't forget to check the Onboard SATA under hard disk Configuration option. If you enable RAID, you will get the S100 controller... let off RAID and use RAID software Windows instead.
achunekeYet once, trying to configure with UEFI boot, he said conflicts in configuration. I am the command without hard drives, but to use an existing drive to 4 TB. I'm going to need to configure GBT and will require UEFI, I think. Is this a problem?You can't order a server without a disk (see below *). If you plan to use your own, order it with the most small/less expensive available drive, then swap later. You have NO need to specify a UEFI/BIOS at the time wherever you order the server if you intend to swap the hard drive or install the OS yourself.
achunekeAnyone aware of any issues with Windows Home Server 2011 running on this platform?I don't see any, other than the fact that he didn't is not officially "supported", so you may run into issues at some point, but I suspect that there won't be any.
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'Real' RAID controllers (like the PERC 6 / i or H700) are not supported in the T110 II, so you don't ' really need to business records. Some have reported PERC 6/7 works to T110 II, but it is not supported, and if you choose to go this route, then make sure you have some good records designed for these controllers.
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Potentially simple Snapshot question
Hello. I think it would be a simple thing to look upward, but for some reason that I can't find the answer to the it.
I am running Vi3 with ESX 3.5i hosts 4. I need to know exactly where a VM snapshot records in. I have a 250 GB drive on an FTP server that I have I envy snapshot in the future. I just formatted a table iSCSI with 440GB LUN. So if a snapshot of my 250 GB drive MUST reside on the same LUN as the original machine, obviously I would not have enough space. Can I choose where to store my snapshots?
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I think that it is possible to change the directory stored in the snapshot, from the command-line editing the VMX file, however I do not recommend to change. I don't remember the exact setting off my head to do it.
See you soon,.
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