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doris/regression-test/data/mtmv_p0
seawinde 0b16938b7f [Fix](Nereids) Fix datatype length wrong when string contains chinese (#29885)
When varchar literal contains chinese, the length of varchar should not be the length of the varchar, it should be 
the actual length of the using byte.
Chinese is represented by unicode, a chinese char occypy 4 byte at mostly. So if meet chinese in varchar literal, we 
set the length is 4* length.

for example as following:
>        CREATE MATERIALIZED VIEW test_varchar_literal_mv
>             BUILD IMMEDIATE REFRESH AUTO ON MANUAL
>             DISTRIBUTED BY RANDOM BUCKETS 2
>             PROPERTIES ('replication_num' = '1')
>             AS
>             select case when l_orderkey > 1 then "一二三四" else "五六七八" end as field_1 from lineitem;

mysql> desc test_varchar_literal_mv;
the def of materialized view is as following:
+---------+-------------+------+-------+---------+-------+
| Field   | Type        | Null | Key   | Default | Extra |
+---------+-------------+------+-------+---------+-------+
| field_1 | VARCHAR(16) | No   | false | NULL    | NONE  |
+---------+-------------+------+-------+---------+-------+
2024-01-16 18:31:59 +08:00
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