# CAST ## description ### Syntax ``` cast (input as type) ``` ### BIGINT type ### Syntax(BIGINT) ``` cast (input as BIGINT) ``` 将 input 转成 指定的 type 将当前列 input 转换为 BIGINT 类型 ## example 1. 转常量，或表中某列 ``` mysql> select cast (1 as BIGINT); +-------------------+ | CAST(1 AS BIGINT) | +-------------------+ | 1 | +-------------------+ ``` 2. 转导入的原始数据 ``` curl --location-trusted -u root: -T ~/user_data/bigint -H "columns: tmp_k1, k1=cast(tmp_k1 as BIGINT)" http://host:port/api/test/bigint/_stream_load ``` *注：在导入中，由于原始类型均为String，将值为浮点的原始数据做 cast的时候数据会被转换成 NULL ，比如 12.0 。Doris目前不会对原始数据做截断。* 如果想强制将这种类型的原始数据 cast to int 的话。请看下面写法： ``` curl --location-trusted -u root: -T ~/user_data/bigint -H "columns: tmp_k1, k1=cast(cast(tmp_k1 as DOUBLE) as BIGINT)" http://host:port/api/test/bigint/_stream_load mysql> select cast(cast ("11.2" as double) as bigint); +----------------------------------------+ | CAST(CAST('11.2' AS DOUBLE) AS BIGINT) | +----------------------------------------+ | 11 | +----------------------------------------+ 1 row in set (0.00 sec) ``` ##keyword CAST