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Re: can this be done in one SQL selcet statement?!

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First, I think the table design is probably not the best way to do this. In the relational database world, Table 2 probably should look like this:

NODE1	NODE2
NODE1	NODE3
NODE2	NODE4
NODE2	NODE3


Then you could do:

INSERT INTO table1 SELECT DISTINCT column2 FROM table2 WHERE column2 NOT IN (SELECT column1 FROM table1);

Greg

sasan3@xxxxxxxxx wrote:

I have two table:
-Table1: one column of type TEXT containing label for nodes in a graph

-Table 2: two columns of type TEXT. first column contains node labels
in a graph. second a list of node labels that the node label in column
one is connected to.

Example:
    Table1:
         "NODE1"
         "NODE2"

    Table 2:
          "NODE1"    "NODE2 NODE3"
          "NODE2"    "NODE4 NODE3"

Goal:
     split column2 in table2 to individual node names, find a unique
list of all node names obtained after splitting column2 of table2 and
insert the ones not already in table1 in table1.


Thanks in advance.

S


---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
       choose an index scan if your joining column's datatypes do not
       match


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