hdfs://YZSJHL19-42.opi.com/warehouse.test/acorn_3g.db/user_act
mysql> select * from SDS where SD_ID=263311 \G
*************************** 1. row ***************************
SD_ID: 263311
CD_ID: 263311
INPUT_FORMAT: org.apache.hadoop.mapred.TextInputFormat
IS_COMPRESSED:
LOCATION: hdfs://YZSJHL19-42.opi.com/warehouse.test/acorn_3g.db/user_act
NUM_BUCKETS: -1
OUTPUT_FORMAT: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat
SERDE_ID: 263301
IS_STOREDASSUBDIRECTORIES:
2.4 CDS 和 COLUMN_V2 (列信息)
CDS表
描述:
该表只有一个字段CD_ID，永远存储整个Hive数据仓库中的CD_ID.
例子:
可以看到acorn_3g.user_act表对应的CD_ID记录在CDS中
mysql> desc CDS;
+-------+------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+------------+------+-----+---------+-------+
| CD_ID | bigint(20) | NO | PRI | NULL | |
+-------+------------+------+-----+---------+-------+
1 row in set (0.00 sec)
mysql> select * FROM CDS where CD_ID=263311;
+--------+
| CD_ID |
+--------+
| 263311 |
+--------+
1 row in set (0.00 sec)
COLUMN_V2表
描述:
该表存储了一个CD_ID对应的所有字段信息
例子:
查看acorn_3g.user_act表的COLUMN信息;我们可以看到acorn_3g.user_act表有14个字段，COLUMN_NAME为字段名，TYPE_NAME为字段类型,INTEGER_IDX为字段序号
mysql> select * from COLUMNS_V2 where CD_ID=263311 order by integer_idx;
+--------+---------+---------------+-----------+-------------+
| CD_ID | COMMENT | COLUMN_NAME | TYPE_NAME | INTEGER_IDX |
+--------+---------+---------------+-----------+-------------+
| 263311 | NULL | id | bigint | 0 |
| 263311 | NULL | action_id | int | 1 |
| 263311 | NULL | user_id | bigint | 2 |
| 263311 | NULL | request | string | 3 |
| 263311 | NULL | visit_time | string | 4 |
| 263311 | NULL | source_id | int | 5 |
| 263311 | NULL | sess_id | string | 6 |
| 263311 | NULL | mobile_number | string | 7 |
| 263311 | NULL | from_id | string | 8 |
| 263311 | NULL | app_id | string | 9 |
| 263311 | NULL | version | string | 10 |
| 263311 | NULL | reg_type | int | 11 |
| 263311 | NULL | uniqid | string | 12 |
| 263311 | NULL | failure | int | 13 |
+--------+---------+---------------+-----------+-------------+
2.5 SERDES和SERDE_PARAMS (序列化)
描述:
SERDES存储了所有的序列化信息(SERDE_ID,SLIB),SLIB表示序列化所采用的
Java类
SERDES_PARAMS 存储序列化具体的参数及值
例子：
acorn_3g.user_act表对应的SERDE_ID=263301表示 采用hive默认序列化类org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe , DELIMITED字符为'\t' (即创建表时指定的 ...DELIMITED BY '\t' ...)
mysql> select * FROM SERDES where SERDE_ID=263301;
+----------+------+----------------------------------------------------+
| SERDE_ID | NAME | SLIB |
+----------+------+----------------------------------------------------+
| 263301 | NULL | org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe |
+----------+------+----------------------------------------------------+
mysql> select SERDE_ID,PARAM_KEY,REPLACE(PARAM_VALUE,'\t','\\t') from SERDE_PARAMS where SERDE_ID=263301;
+----------+----------------------+---------------------------------+
| SERDE_ID | PARAM_KEY | REPLACE(PARAM_VALUE,'\t','\\t') |
+----------+----------------------+---------------------------------+
| 263301 | field.delim | \t |
| 263301 | serialization.format | \t |
+----------+-----------