Join from multiple tables to one column - sql

I have some problem with sql view. I have some element_ids in my based main table. That column is connected with another 3 tables, there ane unique el_id for that 3 tables. I want to joint that three tables in one column taking another id and write in another column which item it is.
Example:
I take el_id=2 from main table, check if it is in table_1, then I check table_2, there is el_id=2, so I get item_id to my view and write the information in type column in my view.

Related

rearrange two columns into single unique rows

I have a table that has two ID fields:
ID_expired
ID_issued
This table is the only place where this link between IDs is recorded. An ID_issued will show up with a match in these ID_expired column when a new ID_issued occurs (e.g. z234, g123). There are some exact duplicate rows. There are also instances where there is a duplicate ID_issued but no ID_expired listed (e.g. b111).
My objective is to connect all the IDs into a single row so I can refer to the ID history of an individual.
You can create a View and add the table to the view for as many times as there are ID's and join it on itself as many times as well.

Power Pivot relationships

Trying to create relationships (joins) between tables in power pivot.
Got 2 tables I wold like to join together, connected with a common column = CustomerID.
One is a Fact Table the other Dim table (look up).
I have run the "remove duplicates" on both tables without any problem.
But I still get an error saying : "the relationship cannot be created because each column contains duplicate values. Select at least one column that contains only unique values".
The Fact Table contains duplicates (as it should?) and the Dim Table do not, why do I get this error?
Help much appreciated
Created an appended table with both columns "CustomerID". After the columns where appended together I could "remove duplicates" and connect the tables together through the newly created appended table.
Don't know if this causes another problem later however.
You can also check for duplicate id values in a column by using the group by feature.
Remove all columns except ID, add a column that consists only of the number 1.
Group by ID, summing the content of the added column and filter out IDs whose total equals 1. What's left are duplicated IDs.

Want to synchronize two table in oracle without using DBMS_COMPARISON

I have two identical tables in the database (Same column name, same data type). Table A and Table B.
A is the master table. Now i want to update the table B with the changes done in the master table A automatically at any point of time. How would i do that without using DBMS_COMPARISON

Merge or Union tables in Access

I have two tables that I would like to combine into an unduplicated list. I have a 'SUB' table that has a 1 column named 'ID' containing a unique identifier for 11,000 some records. I also have another table with 75,000 rows called 'MASTER'. It contains two columns, 'ID' which has the same unique identifier and 'CODE' which contains a unique code for each ID. I want to create a new table that has the 11,000 IDs from the 'SUB' table with the corresponding 'CODE's that match the 'SUB' IDs from the 'MASTER' table. I have used a basic UNION Query, but the results had duplication in the 'ID' column. I tried to consolidate the table produced by that query using Excel, but the list was too long to crunch. Any help? I know this is a basic, but I am not a database person... What would the SQL code look like to achieve this?
Thanks!
You should use JOIN instead of UNION to achieve what you want.
Something like that should work:
SELECT SUB.ID, MASTER.CODE
FROM SUB
JOIN MASTER
ON SUB.ID = MASTER.ID
In general, JOIN allows you to match some rows from one table to the rows from other table according to the value(s) in these rows (think of it as "gluing" rows together along the vertical axis to form longer rows), while what UNION does is just adding all rows from one table below other table (i.e. appends one table to the end of other table along the horizontal axis).

How to append new columns with data from one table to another

I know the title might seem confusing but the real situation is as follow: I have two tables with existing data and both of them have n rows but different columns. The order of the rows in two tables do match. So the goal is such that after appending, the first row of the second table is appended to the first row of the first table, etc. and all the columns from the second table are added to the first table - basically just like paste two tables together.