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Polling data from two tables - heidisql

I am trying to retrieve data from two tables. Following code works fine:

const sql = "SELECT * FROM table_1, table_2 WHERE table_2.Id = table_1.tafId";

But I dont´t want all the data from table_1. I only want the data with the name "something". I tried following code, but it throws an exception:

const sql = "SELECT aa, bb, cc, dd FROM table_1 WHERE aa= '" + something + "', table_2 WHERE table_2.Id = table_1.tafId";

The failure message is:

check the manual that corresponds to your MariaDB server version for the right syntax to use near ' table_2 WHERE table_2.Id = table_1.tafId' at line 1",
  sqlState: '42000',
  index: 0,

What do I miss?

Would be happy for some help. Thanks!

You need to specify column belongs to which table.

or you can make use of alias

Assuming aa column belongs to table_1 and bb column belongs to table_2 , here is the query

const sql = "SELECT table_1.aa, table_2.bb FROM table_1, table_2 WHERE table_2.Id = table_1.tafId";

using alias(alias name can be anything). Here a1 and a2 are alias

const sql = "SELECT a1.aa, a2.bb FROM table_1 a1, table_2 a2 WHERE a1.Id = a2.tafId";

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