The PARSE-AS-SIMPLEDATE directive parses strings with date-time datetime values to the timestamp_micros data type, which is based on the Avro timestamp_micros type.
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The PARSE-AS-SIMPLE-DATE directive will parse a string with date-time datetime values, using a pattern string. If the column is null or has already been parsed as timestamp_micros, applying this directive is a no-op. The column to be parsed as timestamp_micros must be of type string.
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