sqlite - How to know if a row doesn't exist? -


I have the following query: 

  Select row 1 by Random () Limit 1

Also I have another table (Table 3). In that table I have the column table 1_id and the table 2_id is a link of one line in the table 1_id table 1 and the table 2_id is a link of one line in the second table.

I want to achieve only those results in my query that are defined in Table 3. Only those who have table 1 queued in their table 1_id column There can not be any column in the context of a fixed table 1 row, so in this situation I do not want to receive them.

How can I achieve this goal?

Update: I tried the following question, which does not work: 

  Select 1 line from the table, line it in row 1 (Table 1_id to Table 3 Where the table select 1_id = table1.rowid) Random () range 1)  
 
 
 
 
  Select from 1 row in the table where in the queue (choose from Table 3 Table 1_id); Random () range 1 by command;  
 
 This query means "Choose from a random one line from"  table1  "which is the entry  table3 "  ". 
 
 Each row is being selected in Table 1 ( DISTINCT ), as long as it has at least one in  table3  The time is referred to. 
 
 If you are trying to get more than one result, you would get " from command to random () range 1 " section.

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