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Step 1. The LERG table is queried to determine if the NPANXXY for the ANI and DNIS are both in the LERG table. A successful query returns the company, ocn, lata, ratecenter and prefix_type. Specific to local call determination, these values are irrelevant, just the fact the LERG queries return a result is sufficient to move to Step 2. If either query fails to return a result than it is not a local call and the LCAD is not queried.
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