I am running a query that fetches data(records) form a linked table from another database.
The linked table is populated by users using a form remotely, like the web.
I created this piece of code that queries the data from the linked table into a new table, like this:
`INSERT INTO NEW_TBL(ENT_CUS_NUM, ENT_FIRST_NAME, ENT_LAST_NAME, ENT_ADDRESS1, ENT_CITY, ENT_STATE, ENT_ZIP, ENT_PHONE)
SELECT LINK_TBL.CUS_NUM, LINK_TBL.FIRST_NAME, LINK_TBL.LAST_NAME, LINK_TBL.ADDRESS1, LINK_TBL.CITY, LINK_TBL.STATE, LINK_TBL.ZIP, LINK_TBL.PHONE
FROM LINK_TBL`
Is it possible to modify this query so that it inserts new records from the link table if the record has not already been added, or update existent records
that have been modified? Example: Lets say a person changes their address, Can I update or bring over only their address without re-inserting their entire record because of an address change?
This is what confuses, I could write an update statement but modifying this querying so that it brings over new records or update records with changes is way over my head.
I would appreciate your input and help.
Guy
If you can designate a field as a unique key, you can use REPLACE INTO instead of INSERT INTO at least with mysql
Related
I'm very new to database/server management. I'm working with a database that I can't add any columns to since it interfaces directly with another piece of software and therefore must stay in a very specific format. However, I'd like to be able to add DateCreated, and CreatedBy columns to the tables in this database to setup some automatic email updates when new entries are made. To do this, I thought I might be able to keep a copy of the original database that automatically updates when changes are made to the original and simply add the additional columns to the copy. I'm working in Microsoft SQL 2017. If anyone could provide any guidance on the best way to accomplish this, your help would be much appreciated.
Create a table extension that consists of the additional columns + the key value from the original table. Each row in Table 1 should have 1 or 0 rows in Table 2. Use a trigger on Table 1 to insert a row in Table 2 on Insert or Update.
I want to run a delete query to remove certain data from a table in a Sharepoint list using an MS Access query. However I want to be sure only to delete from a single list based on the values of another table.
The table is TMainData: This consists solely of number fields that are references to the keyfields in other tables, such as TProgram which has a program name, or TContact which has the point of contact, or TPositionTitle which has a title like Site Director.
So a TMainData entry looks something like
ProgramID, which links to TPrograms: 4
ContactID, which links to TContacts: 42
PositionTitle, which links to TPositionTitle: 3
This tells me that the Site Director (TPositionTitle 3) of Anesthesiology (ProgramID 4) is John Smith (ContactID 42).
Here's where it gets tricky: I have a reference under TPrograms to TProgramType. I want to delete all records under TMainData where they link to a certain Program Type, because that program type is going away. HOWEVER... I don't want to delete the program itself (yet), just the lines referencing that program in TMainData.
The "manual" way I see to do this is to run queries that identify what the ProgramIDs are of the programs I want to delete the contacts for, and then use those IDs in a delete query that only references the TMainData query. I'm wondering if there's a way to use referential data, because I may have to be running some ridiculous update queries at a later time that would need this same info.
I dug through https://support.office.com/en-us/article/Use-queries-to-delete-one-or-more-records-from-a-database-A323BF1A-C9B4-4C86-8719-BE58BDF1B10C but it doesn't seem to cover deleting from one table based on values referenced in another table.
You already seem to understand what you need to do to achieve the desired result when you state:
...run queries that identify what the ProgramIDs are of the programs I want to delete the contacts for, and then use those IDs in a delete query that only references the TMainData query.
If I've understood your description correctly, I would suggest something along the lines of:
delete from tmaindata
where
tmaindata.programid in
(
select tprograms.programid
from tprograms
where tprograms.tprogramtype = 'YourProgramType'
)
Always take a backup of your data before running delete queries - there is no undo.
Table will be getting new data everyday from source system and i want the duplicates to be deleted automatically as soon as new data gets loaded to table.
Is it possible in bigquery?
I tried to create a view named sites_view in bigquery with below query
SELECT DISTINCT * FROM prd.sites
but duplicates not getting deleted automatically.
Below is for BigQuery:
Duplicates will not be deleted automatically - there is no such functionality in BigQuery
You should have some process to make this happen as frequently as you need or use views
Bigquery is based on append-only kind of a design. So, it accepts all the data.
This is one of the reasons there are no Primary/Unique key constraints on it, so you can't prevent duplicates from entering in the table.
So, you have to have a process like:
1.) Create a new table without duplicates from your original table.
(You can use DISTINCT/ROW_NUMBER() for doing this.)
2.) Drop original table.
3.) Rename new table with original table name.
Let me know if this information helps.
The only way I can think of doing it, since what I want to do is have a database of all the companies, and their respective information, then have another database per each company that sorts their orders and jobs, Is there a cleaner way than creating a table for each element in the company list table? If not, how would I go about doing this?
create trigger on yourdb for insert
then inside the trigger
create table and insert int it the specific row
Your question is a bit confusing. It seems that you may want to add the company id as a key on all the relations that exist. This would allow you to keep various company information in the same table structure and select from it by filtering on the company id.
say I have 6 tables.
Workstation
Workstation_CL
Location
Location_CL
Features
Features_CL
I am currently using triggers to do inserts into the "_CL" version of each table with an additional field that denotes whether the change was an "UPDATE", "INSERT" or "DELETE".
the workstation table keeps track of the "modified_by" user. if a user updates the location of a "Workstation" object, the "Location" table gets updated as well as the "Workstation" table. the only modification to the Workstation table is the "modified_by" field so that I will know who made the change.
The problem I am having is when I think about pulling an audit report. How will I link records in the "Location_CL" to the ones in the "Workstation_CL" both are populated by separate triggers.
somehow my question portion was erased. sorry about that.
Question: how can I pull some type of unique identifier to have in both the "Workstation_CL" and the "Location_CL" so that I can identify each revision? for instance, when I pull all records from the "Location_CL" and I see all location changes, pulling the username from the "Workstation_CL" that made the location change?
Give each revision a GUID generated by the trigger. Populate a field (RevisionId) in both tables with the value.
You need 2, maybe 3 columns on each audit table.
1) Timestamp, so you know when the changes were made.
2) User changed, so you can track who made the changes - I assume that Location can change independently of Workstation.
3) You might need an identifier for the transaction, too. I THINK you can get an id from the DB, though I'm not sure.
I don't think you can have an effective report without timestamps and users, though, and I don't think you just have the user on one table.
During the trigger event, I was able to exec the following:
SELECT #trans_id=transaction_id FROM sys.dm_tran_current_transaction
which gives me the transaction id for the current operation.
with that, I am able to insert it in to the corresponding _CL table and then perform selects that will match the auto-gen id's.