MAP
MAP<K, V>
A Map of K, V items, it cannot be used as a key column. Now MAP can only used in Duplicate and Unique Model Tables.
K,V could be any of:
BOOLEAN, TINYINT, SMALLINT, INT, BIGINT, LARGEINT, FLOAT, DOUBLE, DECIMAL, DECIMALV3, DATE,
DATEV2, DATETIME, DATETIMEV2, CHAR, VARCHAR, STRING
CSV format importβ
Step 1: Prepare the dataβ
Create the following csv file: test_map.csv
The separator is |
instead of comma to distinguish it from the comma in map.
1|{"Emily":101,"age":25}
2|{"Benjamin":102}
3|{}
4|null
Step 2: Create a table in the databaseβ
CREATE TABLE map_test (
id INT NOT NULL,
c_map MAP<STRING, INT> NULL
)
DUPLICATE KEY(id)
DISTRIBUTED BY HASH(id) BUCKETS 1
PROPERTIES (
"replication_allocation" = "tag.location.default: 1"
);
Step 3: Load dataβ
curl --location-trusted \
-u "root":"" \
-H "column_separator:|" \
-H "columns: id, c_map" \
-T "test_map.csv" \
http://localhost:8040/api/testdb/map_test/_stream_load
Step 4: Check the imported dataβ
mysql> SELECT * FROM map_test;
+------+-------------------------+
| id | c_map |
+------+-------------------------+
| 1 | {"Emily":101, "age":25} |
| 2 | {"Benjamin":102} |
| 3 | {} |
| 4 | NULL |
+------+-------------------------+
4 rows in set (0.01 sec)
JSON format importβ
Step 1: Prepare the dataβ
Create the following JSON file, test_map.json
[
{"id":1, "c_map":{"Emily":101, "age":25}},
{"id":2, "c_map":{"Benjamin":102}},
{"id":3, "c_map":{}},
{"id":4, "c_map":null}
]
Step 2: Create a table in the databaseβ
CREATE TABLE map_test (
id INT NOT NULL,
c_map MAP<STRING, INT> NULL
)
DUPLICATE KEY(id)
DISTRIBUTED BY HASH(id) BUCKETS 1
PROPERTIES (
"replication_allocation" = "tag.location.default: 1"
);
Step 3: Load dataβ
curl --location-trusted \
-u "root":"" \
-H "format:json" \
-H "columns: id, c_map" \
-H "strip_outer_array:true" \
-T "test_map.json" \
http://localhost:8040/api/testdb/map_test/_stream_load
Step 4: Check the imported dataβ
mysql> SELECT * FROM map_test;
+------+-------------------------+
| id | c_map |
+------+-------------------------+
| 1 | {"Emily":101, "age":25} |
| 2 | {"Benjamin":102} |
| 3 | {} |
| 4 | NULL |
+------+-------------------------+
4 rows in set (0.01 sec)