Add table B row to table A based on conditions

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I have two tables of data, being them: table A and table B. I want to join the rows of table B with A under the following conditions:

If a line occurs in B and not in A, add it to A. If a line occurs more in B than in A, add it to A until it occurs as often in A as in B. If I have the following two tables:

TabelaA TabelaB 2 4 1 3 2 2 2 1 2 2 2 1 2 4 1 3 4 5 2 4 2 4 1 3 1 4 2 5 2 4 1 3 2 4 1 3 5 3 2 3

I want to have the following table:

Tabela A + B 2 2 2 1 2 4 1 3 2 4 1 3 2 4 1 3 4 5 2 4 1 4 2 5 5 3 2 3

You can achieve this with an sql query?

sql database

  • Are each of the table elements in a different column? For example, the first row of the table A, "2 4 1 3", are 4 different columns?

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If a line occurs in B and not in A, add it to A.

You solve this with set theory. Just do 

A U (B - A)

which is implemented in SQL by

-- código #1
SELECT distinct A1, A2, A3, A4 from B
minus 
SELECT distinct B1, B2, B3, B4 from A;

The above code lists the first part of which should be added in A.
Depending on the database manager it is not necessary to use the DISTINCT clause.

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