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How to get faster output on SQL query to join four tables

SQL query is joining four tables in a WHERE clause. Three tables are very small but one table has a very large number of rows (2.5 milion rows). The execution plan shows an index unique scan on small tables, and an index range scan on a large table. The query takes more than one hour to show the output. I need the output within 30 minutes.
Are the join columns all indexed? Does the query specify the join correctly? Thirty minutes is excessive, even with a 2.5-million row table. You should experiment with the use of different indexes and with optimizer hints to force different join orders and join algorithms.

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