how to exclude null values in array_agg like in string_agg using postgres?

how to exclude null values in array_agg like in string_agg using postgres?

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How to create an "on-the-fly" mapping table within a SELECT statement in Postgresql

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Tricky logical XOR for nullable values

sql postgresql postgresql-8.4

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Aggregate strings in descending order in a PostgreSQL query

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Fetch records that are non zero after the decimal point in PostgreSQL

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SQL: Select (null = null);

sql postgresql-8.4

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