database - SQL conceptional: how many ways to "add" column and row to a result set? -

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I am currently learning SQL

The column and row from the result set to get the desired data mainly "cutting" (with its section) SQL

It seems that there are only two ways to add "column" column: 

  Join the table. 2. Select the "virtual" column in the selection list.   
 And we can only add "rows":  
  1   
 
 you   like call 1, now () as col2 ... to   
 etc.  
 Rows can be added by adding new tables or just FOR in the table or sub-selections  
  select from table 1 (select 1 union 2) line 2 Choose the second row in the table # 2 rows doubles

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