Basic use of Hive
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Hive has three complex data types: ARRAY, MAP, and STRUCT. ARRAY and MAP are similar to Array and Map in Java, while STRUCT, like Struct in C, encapsulates a collection of named fields, and complex data types allow for any level of nesting.
Create a datasheet
Create table test (name string,friends array,children map,address struct) row format delimited fields terminated by', 'collection items terminated by' _ 'map keys terminated by': 'lines terminated by'\ n
View data structures
Hive (default) > desc test;OKcol_name data_type commentname string friends array children map address struct Time taken: 0.053 seconds, Fetched: 4 row (s)
test data
Liming,zhangsan_lisi,xiao ming:12_xiaoxiao ming:3,haidian_beijingwangwu,zhaoliu_sunba_qianer,xiao wang:18_xiaoxiao wang:9,chao yang_beijing
Load test data
Hive (default) > load data local inpath'/ opt/module/data/people.txt' into table test;Loading data to table default.testTable default.test stats: [numFiles=1, numRows=0, totalSize=141, rawDataSize=0] OKTime taken: 0.354 seconds
View data content
Hive (default) > select * from test;OKtest.name test.friends test.children test.addressliming ["zhangsan", "lisi"] {"xiao ming": 12, "xiaoxiao ming": 3} {"street": "haidian", "city": "beijing"} wangwu ["zhaoliu", "sunba", "qianer"] {"xiao wang": 18, "xiaoxiao wang": 9} {"street": "chao yang", "city": "beijing"} Time taken: 0.069 seconds, Fetched: 2 row (s)
# # Mysql to view the structure of hive table
View the fields of the table
# # loading data into hive
LOAD DATA LOCAL (local files need to add LOCAL) INPATH 'file path' OVERWRITE INTO TABLE table name
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