1.doris表基本概念
- 在 Doris 中,数据都以关系表(Table)的形式进行逻辑上的描述。
1.1.1Row & Column
- 一张表包括行(Row)和列(Column)
- Row 即用户的一行数据
- Column 用于描述一行数据中不同的字段
- 在
默认的数据模型中,Column 只分为排序列和非排序列
。存储引擎会按照排序列对数据进行排序存储,并建立稀疏索引,以便在排序数据上进行快速查找。 - 而在
聚合模型中,Column 可以分为两大类:Key 和 Value
。从业务角度看,Key 和Value 可以分别对应维度列和指标列。从聚合模型的角度来说,Key 列相同的行,会聚合成一行。其中 Value 列的聚合方式由用户在建表时指定。
- 在
1.1.2Partition & Tablet
- 在 Doris 的存储引擎中,
用户数据首先被划分成若干个分区(Partition),划分的规则通常是按照用户指定的
分区列进行范围划分,比如按时间划分
。而在每个分区内,数据被进一步的按照 Hash 的方式分桶,分桶的规则是要找用户指定的
分桶列的值进行 Hash 后分桶
。每个分桶就是一个数据分片(Tablet),也是数据划分的最小逻辑单元。 - Tablet 之间的数据是
没有交集
的,独立存储
的。Tablet 也是数据移动、复制
等操作的最小物理存储单元
。 - Partition 可以视为是
逻辑上最小的管理单元
。数据的导入与删除,都可以或仅能针
对一个 Partition 进行。
2.doris字段类型
字段类型 | ||
---|---|---|
TINYINT | 1 字节 | 范围:-2^7 + 1 ~ 2^7 - 1 |
SMALLINT | 2 字节 | 范围:-2^15 + 1 ~ 2^15 - 1 |
INT | 4 字节 | 范围:-2^31 + 1 ~ 2^31 - 1 |
BIGINT | 8 字节 | 范围:-2^63 + 1 ~ 2^63 - 1 |
LARGEINT | 16 字节 | 范围:-2^127 + 1 ~ 2^127 - 1 |
FLOAT | 4 字节 | 支持科学计数法 |
DOUBLE | 12 字节 | 支持科学计数法 |
DECIMAL(M[,D]) | 16 字节 | “默认是DECIMAL(9, 0)高精度定点数,M 代表一共有多少个有效数字(precision),D 代表小数位有多少数字(scale),有效数字 M 的范围是 [1, 27],小数位数字数量 D 的范围是 [0, 9],整数位数字数量的范围是 [1, 18],另外,M 必须要大于等于 D 的取值。” |
DECIMALV3(M[,D]) | Doris中的DECIMALV3是真正意义上的高精度定点数,相比于老版本的Decimal 1.可表示范围更大,有效数字 M 的范围是 [1, 38],小数位数字数量 D 的范围是 [0, precision]。2.性能更高。老版本的DECIMAL在内存中需要占用16 bytes,在存储中占用12 bytes,而DECIMALV3进行了自适应调整。3.更完备的精度推演。对于不同的表达式,应用不同的精度推演规则对结果的精度进行推演。 | |
DATE | 3 字节 | 范围:0000-01-01 ~ 9999-12-31 |
DATEV2 | DATEV2类型相比DATE类型更加高效,在计算时,DATEV2相比DATE可以节省一半的内存使用量。 | |
DATETIME | 8 字节 | 范围:0000-01-01 00:00:00 ~ 9999-12-31 23:59:59 |
DATETIMEV2([P]) | 可选参数P表示时间精度,取值范围是[0, 6],即最多支持6位小数(微秒)。不设置时为0。取值范围是[‘0000-01-01 00:00:00[.000000]’, ‘9999-12-31 23:59:59[.999999]’] 相比DATETIME类型,DATETIMEV2更加高效,并且支持了最多到微秒的时间精度。 | |
CHAR[(length)] | 定长字符串。长度范围:1 ~ 255。默认为 1 | |
VARCHAR[(length)] | 变长字符串。长度范围:1 ~ 65533 注意:变长字符串是以UTF-8编码存储的,因此通常英文字符占1个字节,中文字符占3个字节。 | |
BOOLEAN | 与 TINYINT 一样,0 代表 false,1 代 表 true | |
HLL | 1~16385 个字节 | HLL不能作为key列使用,建表时配合聚合类型为HLL_UNION。用户不需要指定长度和默认值。长度根据数据的聚合程度系统内控制。并且HLL列只能通过配套的hll_union_agg、hll_raw_agg、hll_cardinality、hll_hash进行查询或使用。HLL是模糊去重,在数据量大的情况性能优于Count Distinct。HLL的误差通常在1%左右,有时会达到2%。
|
BITMAP | 1.不能作为key列使用,建表时配合聚合类型为BITMAP_UNION。2.用户不需要指定长度和默认值。长度根据数据的聚合程度系统内控制。 3.BITMAP列只能通过配套的bitmap_union_count、bitmap_union、bitmap_hash等函数进行查询或使用。4.离线场景下使用BITMAP会影响导入速度,在数据量大的情况下查询速度会慢于HLL,并优于Count Distinct。5.注意:实时场景下BITMAP如果不使用全局字典,使用了bitmap_hash()可能会导致有千分之一左右的误差。 | |
STRING | 变长字符串,0.15 版本支持,最大支持 2147483643 字节(2GB-4),长度还受 be 配置string_type_soft_limit , 实际能存储的最大长度取两者最小值。只能用在 value 列,不能用在 key 列和分区、分桶列。 注意:变长字符串是以UTF-8编码存储的,因此通常英文字符占1个字节,中文字符占3个字节。 |
|
ARRAY<T> | 由T类型元素组成的数组,不能作为key列使用。目前支持在Duplicate模型的表中使用。T支持的类型有:BOOLEAN, TINYINT, SMALLINT, INT, BIGINT, LARGEINT, FLOAT, DOUBLE, DECIMAL, DATE,DATEV2, DATETIME, DATETIMEV2, CHAR, VARCHAR, STRING | |
QUANTILE_STATE | QUANTILE_STATE不能作为key列使用,建表时配合聚合类型为QUANTILE_UNION。用户不需要指定长度和默认值。长度根据数据的聚合程度系统内控制。并且QUANTILE_STATE列只能通过配套的QUANTILE_PERCENT、QUANTILE_UNION、TO_QUANTILE_STATE等函数进行查询或使用。QUANTILE_STATE 是一种计算分位数近似值的类型,在导入时会对相同的key,不同 value 进行预聚合,当value数量不超过2048时采用明细记录所有数据,当 value 数量大于2048时采用 TDigest 算法,对数据进行聚合(聚类)保存聚类后的质心点。 | |
JSONB | JSONB(JSON Binary)类型 二进制JSON类型,采用二进制JSONB格式存储,通过jsonb函数访问JSON内部字段。与普通STRING类型存储的JSON字符串相比,JSONB类型有两点优势1. 数据写入时进行JSON格式校验2. 二进制存储格式更加高效,通过jsonb_extract等函数可以高效访问JSON内部字段,比get_json_xx函数快几倍 |
- bitmap使用场景
select hour
,bitmap_union_count(pv) over(order by hour) uv
from
(
select hour
,bitmap_union(device_id) as pv
from metric_table -- 查询每小时的累计UV
where datekey = 20200622
group by hour
order by 1
) final
;
- hll 使用场景
select hour
,hll_union_agg(pv) over(order by hour) uv
from
(
select hour
,hll_raw_agg(device_id) as pv
from metric_table -- 查询每小时的累计uv
where datekey = 20200622
group by hour
order by 1
) final
;
- ARRAY<T>使用场景
建表示例如下:
mysql> CREATE TABLE `array_test` (
`id` int(11) NULL COMMENT "",
`c_array` ARRAY<int(11)> NULL COMMENT ""
) ENGINE=OLAP
DUPLICATE KEY(`id`)
COMMENT "OLAP"
DISTRIBUTED BY HASH(`id`) BUCKETS 1
PROPERTIES (
"replication_allocation" = "tag.location.default: 1",
"in_memory" = "false",
"storage_format" = "V2"
);
插入数据示例:
mysql> INSERT INTO `array_test` VALUES (1, [1,2,3,4,5]);
mysql> INSERT INTO `array_test` VALUES (2, [6,7,8]), (3, []), (4, null);
查询数据示例:
mysql> SELECT * FROM `array_test`;
+------+-----------------+
| id | c_array |
+------+-----------------+
| 1 | [1, 2, 3, 4, 5] |
| 2 | [6, 7, 8] |
| 3 | [] |
| 4 | NULL |
+------+-----------------+
- JSONB 使用场景
设置容错率参数 'max_filter_ratio: 0.3'
curl --location-trusted -u root: -H 'max_filter_ratio: 0.3' -T test_jsonb.csv http://127.0.0.1:8840/api/testdb/test_jsonb/_stream_load
{
"TxnId": 12017,
"Label": "f37a50c1-43e9-4f4e-a159-a3db6abe2579",
"TwoPhaseCommit": "false",
"Status": "Success",
"Message": "OK",
"NumberTotalRows": 25,
"NumberLoadedRows": 18,
"NumberFilteredRows": 7,
"NumberUnselectedRows": 0,
"LoadBytes": 380,
"LoadTimeMs": 68,
"BeginTxnTimeMs": 0,
"StreamLoadPutTimeMs": 2,
"ReadDataTimeMs": 0,
"WriteDataTimeMs": 45,
"CommitAndPublishTimeMs": 19,
"ErrorURL": "http://172.21.0.5:8840/api/_load_error_log?file=__shard_0/error_log_insert_stmt_a1463f98a7b15caf-c79399b920f5bfa3_a1463f98a7b15caf_c79399b920f5bfa3"
}
查看stream load导入的数据,JSONB类型的列j会自动转成JSON string展示
mysql> SELECT * FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+
| id | j |
+------+---------------------------------------------------------------+
| 1 | NULL |
| 2 | null |
| 3 | true |
| 4 | false |
| 5 | 100 |
| 6 | 10000 |
| 7 | 1000000000 |
| 8 | 1152921504606846976 |
| 9 | 6.18 |
| 10 | "abcd" |
| 11 | {} |
| 12 | {"k1":"v31","k2":300} |
| 13 | [] |
| 14 | [123,456] |
| 15 | ["abc","def"] |
| 16 | [null,true,false,100,6.18,"abc"] |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} |
+------+---------------------------------------------------------------+
18 rows in set (0.03 sec)
insert into 插入数据
insert 1条数据,总数据从18条增加到19条
mysql> INSERT INTO test_jsonb VALUES(26, '{"k1":"v1", "k2": 200}');
Query OK, 1 row affected (0.09 sec)
{'label':'insert_4ece6769d1b42fd_ac9f25b3b8f3dc02', 'status':'VISIBLE', 'txnId':'12016'}
mysql> SELECT * FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+
| id | j |
+------+---------------------------------------------------------------+
| 1 | NULL |
| 2 | null |
| 3 | true |
| 4 | false |
| 5 | 100 |
| 6 | 10000 |
| 7 | 1000000000 |
| 8 | 1152921504606846976 |
| 9 | 6.18 |
| 10 | "abcd" |
| 11 | {} |
| 12 | {"k1":"v31","k2":300} |
| 13 | [] |
| 14 | [123,456] |
| 15 | ["abc","def"] |
| 16 | [null,true,false,100,6.18,"abc"] |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} |
| 26 | {"k1":"v1","k2":200} |
+------+---------------------------------------------------------------+
19 rows in set (0.03 sec)
查询
用jsonb_extract取json内的某个字段
获取整个json,$ 在json path中代表root,即整个json
+------+---------------------------------------------------------------+---------------------------------------------------------------+
| id | j | jsonb_extract(`j`, '$') |
+------+---------------------------------------------------------------+---------------------------------------------------------------+
| 1 | NULL | NULL |
| 2 | null | null |
| 3 | true | true |
| 4 | false | false |
| 5 | 100 | 100 |
| 6 | 10000 | 10000 |
| 7 | 1000000000 | 1000000000 |
| 8 | 1152921504606846976 | 1152921504606846976 |
| 9 | 6.18 | 6.18 |
| 10 | "abcd" | "abcd" |
| 11 | {} | {} |
| 12 | {"k1":"v31","k2":300} | {"k1":"v31","k2":300} |
| 13 | [] | [] |
| 14 | [123,456] | [123,456] |
| 15 | ["abc","def"] | ["abc","def"] |
| 16 | [null,true,false,100,6.18,"abc"] | [null,true,false,100,6.18,"abc"] |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | [{"k1":"v41","k2":400},1,"a",3.14] |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} |
| 26 | {"k1":"v1","k2":200} | {"k1":"v1","k2":200} |
+------+---------------------------------------------------------------+---------------------------------------------------------------+
19 rows in set (0.03 sec)
获取k1字段,没有k1字段的行返回NULL
mysql> SELECT id, j, jsonb_extract(j, '$.k1') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+----------------------------+
| id | j | jsonb_extract(`j`, '$.k1') |
+------+---------------------------------------------------------------+----------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | "v31" |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | "v31" |
| 26 | {"k1":"v1","k2":200} | "v1" |
+------+---------------------------------------------------------------+----------------------------+
19 rows in set (0.03 sec)
获取顶层数组的第0个元素
mysql> SELECT id, j, jsonb_extract(j, '$[0]') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+----------------------------+
| id | j | jsonb_extract(`j`, '$[0]') |
+------+---------------------------------------------------------------+----------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | NULL |
| 13 | [] | NULL |
| 14 | [123,456] | 123 |
| 15 | ["abc","def"] | "abc" |
| 16 | [null,true,false,100,6.18,"abc"] | null |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | {"k1":"v41","k2":400} |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | NULL |
| 26 | {"k1":"v1","k2":200} | NULL |
+------+---------------------------------------------------------------+----------------------------+
19 rows in set (0.03 sec)
获取整个json array
mysql> SELECT id, j, jsonb_extract(j, '$.a1') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+------------------------------------+
| id | j | jsonb_extract(`j`, '$.a1') |
+------+---------------------------------------------------------------+------------------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | NULL |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | [{"k1":"v41","k2":400},1,"a",3.14] |
| 26 | {"k1":"v1","k2":200} | NULL |
+------+---------------------------------------------------------------+------------------------------------+
19 rows in set (0.02 sec)
获取json array中嵌套object的字段
mysql> SELECT id, j, jsonb_extract(j, '$.a1[0]'), jsonb_extract(j, '$.a1[0].k1') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+-------------------------------+----------------------------------+
| id | j | jsonb_extract(`j`, '$.a1[0]') | jsonb_extract(`j`, '$.a1[0].k1') |
+------+---------------------------------------------------------------+-------------------------------+----------------------------------+
| 1 | NULL | NULL | NULL |
| 2 | null | NULL | NULL |
| 3 | true | NULL | NULL |
| 4 | false | NULL | NULL |
| 5 | 100 | NULL | NULL |
| 6 | 10000 | NULL | NULL |
| 7 | 1000000000 | NULL | NULL |
| 8 | 1152921504606846976 | NULL | NULL |
| 9 | 6.18 | NULL | NULL |
| 10 | "abcd" | NULL | NULL |
| 11 | {} | NULL | NULL |
| 12 | {"k1":"v31","k2":300} | NULL | NULL |
| 13 | [] | NULL | NULL |
| 14 | [123,456] | NULL | NULL |
| 15 | ["abc","def"] | NULL | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | {"k1":"v41","k2":400} | "v41" |
| 26 | {"k1":"v1","k2":200} | NULL | NULL |
+------+---------------------------------------------------------------+-------------------------------+----------------------------------+
19 rows in set (0.02 sec)
获取具体类型的
jsonb_extract_string 获取string类型字段,非string类型转成string
mysql> SELECT id, j, jsonb_extract_string(j, '$') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+---------------------------------------------------------------+
| id | j | jsonb_extract_string(`j`, '$') |
+------+---------------------------------------------------------------+---------------------------------------------------------------+
| 1 | NULL | NULL |
| 2 | null | null |
| 3 | true | true |
| 4 | false | false |
| 5 | 100 | 100 |
| 6 | 10000 | 10000 |
| 7 | 1000000000 | 1000000000 |
| 8 | 1152921504606846976 | 1152921504606846976 |
| 9 | 6.18 | 6.18 |
| 10 | "abcd" | abcd |
| 11 | {} | {} |
| 12 | {"k1":"v31","k2":300} | {"k1":"v31","k2":300} |
| 13 | [] | [] |
| 14 | [123,456] | [123,456] |
| 15 | ["abc","def"] | ["abc","def"] |
| 16 | [null,true,false,100,6.18,"abc"] | [null,true,false,100,6.18,"abc"] |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | [{"k1":"v41","k2":400},1,"a",3.14] |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} |
| 26 | {"k1":"v1","k2":200} | {"k1":"v1","k2":200} |
+------+---------------------------------------------------------------+---------------------------------------------------------------+
19 rows in set (0.02 sec)
mysql> SELECT id, j, jsonb_extract_string(j, '$.k1') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+-----------------------------------+
| id | j | jsonb_extract_string(`j`, '$.k1') |
+------+---------------------------------------------------------------+-----------------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | v31 |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | v31 |
| 26 | {"k1":"v1","k2":200} | v1 |
+------+---------------------------------------------------------------+-----------------------------------+
19 rows in set (0.03 sec)
jsonb_extract_int 获取int类型字段,非int类型返回NULL
mysql> SELECT id, j, jsonb_extract_int(j, '$') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+-----------------------------+
| id | j | jsonb_extract_int(`j`, '$') |
+------+---------------------------------------------------------------+-----------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | 100 |
| 6 | 10000 | 10000 |
| 7 | 1000000000 | 1000000000 |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | NULL |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | NULL |
| 26 | {"k1":"v1","k2":200} | NULL |
+------+---------------------------------------------------------------+-----------------------------+
19 rows in set (0.02 sec)
mysql> SELECT id, j, jsonb_extract_int(j, '$.k2') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+--------------------------------+
| id | j | jsonb_extract_int(`j`, '$.k2') |
+------+---------------------------------------------------------------+--------------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | 300 |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | 300 |
| 26 | {"k1":"v1","k2":200} | 200 |
+------+---------------------------------------------------------------+--------------------------------+
19 rows in set (0.03 sec)
jsonb_extract_bigint 获取bigint类型字段,非bigint类型返回NULL
mysql> SELECT id, j, jsonb_extract_bigint(j, '$') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+--------------------------------+
| id | j | jsonb_extract_bigint(`j`, '$') |
+------+---------------------------------------------------------------+--------------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | 100 |
| 6 | 10000 | 10000 |
| 7 | 1000000000 | 1000000000 |
| 8 | 1152921504606846976 | 1152921504606846976 |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | NULL |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | NULL |
| 26 | {"k1":"v1","k2":200} | NULL |
+------+---------------------------------------------------------------+--------------------------------+
19 rows in set (0.03 sec)
mysql> SELECT id, j, jsonb_extract_bigint(j, '$.k2') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+-----------------------------------+
| id | j | jsonb_extract_bigint(`j`, '$.k2') |
+------+---------------------------------------------------------------+-----------------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | 300 |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | 300 |
| 26 | {"k1":"v1","k2":200} | 200 |
+------+---------------------------------------------------------------+-----------------------------------+
19 rows in set (0.02 sec)
jsonb_extract_double 获取double类型字段,非double类型返回NULL
mysql> SELECT id, j, jsonb_extract_double(j, '$') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+--------------------------------+
| id | j | jsonb_extract_double(`j`, '$') |
+------+---------------------------------------------------------------+--------------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | 100 |
| 6 | 10000 | 10000 |
| 7 | 1000000000 | 1000000000 |
| 8 | 1152921504606846976 | 1.152921504606847e+18 |
| 9 | 6.18 | 6.18 |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | NULL |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | NULL |
| 26 | {"k1":"v1","k2":200} | NULL |
+------+---------------------------------------------------------------+--------------------------------+
19 rows in set (0.02 sec)
mysql> SELECT id, j, jsonb_extract_double(j, '$.k2') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+-----------------------------------+
| id | j | jsonb_extract_double(`j`, '$.k2') |
+------+---------------------------------------------------------------+-----------------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | 300 |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | 300 |
| 26 | {"k1":"v1","k2":200} | 200 |
+------+---------------------------------------------------------------+-----------------------------------+
19 rows in set (0.03 sec)
jsonb_extract_bool 获取bool类型字段,非bool类型返回NULL
mysql> SELECT id, j, jsonb_extract_bool(j, '$') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+------------------------------+
| id | j | jsonb_extract_bool(`j`, '$') |
+------+---------------------------------------------------------------+------------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | 1 |
| 4 | false | 0 |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | NULL |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | NULL |
| 26 | {"k1":"v1","k2":200} | NULL |
+------+---------------------------------------------------------------+------------------------------+
19 rows in set (0.01 sec)
mysql> SELECT id, j, jsonb_extract_bool(j, '$[1]') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+---------------------------------+
| id | j | jsonb_extract_bool(`j`, '$[1]') |
+------+---------------------------------------------------------------+---------------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | NULL |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | 1 |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | NULL |
| 26 | {"k1":"v1","k2":200} | NULL |
+------+---------------------------------------------------------------+---------------------------------+
19 rows in set (0.01 sec)
jsonb_extract_isnull 获取json null类型字段,null返回1,非null返回0
需要注意的是json null和SQL NULL不一样,SQL NULL表示某个字段的值不存在,而json null表示值存在但是是一个特殊值null
mysql> SELECT id, j, jsonb_extract_isnull(j, '$') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+--------------------------------+
| id | j | jsonb_extract_isnull(`j`, '$') |
+------+---------------------------------------------------------------+--------------------------------+
| 1 | NULL | NULL |
| 2 | null | 1 |
| 3 | true | 0 |
| 4 | false | 0 |
| 5 | 100 | 0 |
| 6 | 10000 | 0 |
| 7 | 1000000000 | 0 |
| 8 | 1152921504606846976 | 0 |
| 9 | 6.18 | 0 |
| 10 | "abcd" | 0 |
| 11 | {} | 0 |
| 12 | {"k1":"v31","k2":300} | 0 |
| 13 | [] | 0 |
| 14 | [123,456] | 0 |
| 15 | ["abc","def"] | 0 |
| 16 | [null,true,false,100,6.18,"abc"] | 0 |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | 0 |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | 0 |
| 26 | {"k1":"v1","k2":200} | 0 |
+------+---------------------------------------------------------------+--------------------------------+
19 rows in set (0.03 sec)
用jsonb_exists_path检查json内的某个字段是否存在
mysql> SELECT id, j, jsonb_exists_path(j, '$') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+-----------------------------+
| id | j | jsonb_exists_path(`j`, '$') |
+------+---------------------------------------------------------------+-----------------------------+
| 1 | NULL | NULL |
| 2 | null | 1 |
| 3 | true | 1 |
| 4 | false | 1 |
| 5 | 100 | 1 |
| 6 | 10000 | 1 |
| 7 | 1000000000 | 1 |
| 8 | 1152921504606846976 | 1 |
| 9 | 6.18 | 1 |
| 10 | "abcd" | 1 |
| 11 | {} | 1 |
| 12 | {"k1":"v31","k2":300} | 1 |
| 13 | [] | 1 |
| 14 | [123,456] | 1 |
| 15 | ["abc","def"] | 1 |
| 16 | [null,true,false,100,6.18,"abc"] | 1 |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | 1 |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | 1 |
| 26 | {"k1":"v1","k2":200} | 1 |
+------+---------------------------------------------------------------+-----------------------------+
19 rows in set (0.02 sec)
mysql> SELECT id, j, jsonb_exists_path(j, '$.k1') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+--------------------------------+
| id | j | jsonb_exists_path(`j`, '$.k1') |
+------+---------------------------------------------------------------+--------------------------------+
| 1 | NULL | NULL |
| 2 | null | 0 |
| 3 | true | 0 |
| 4 | false | 0 |
| 5 | 100 | 0 |
| 6 | 10000 | 0 |
| 7 | 1000000000 | 0 |
| 8 | 1152921504606846976 | 0 |
| 9 | 6.18 | 0 |
| 10 | "abcd" | 0 |
| 11 | {} | 0 |
| 12 | {"k1":"v31","k2":300} | 1 |
| 13 | [] | 0 |
| 14 | [123,456] | 0 |
| 15 | ["abc","def"] | 0 |
| 16 | [null,true,false,100,6.18,"abc"] | 0 |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | 0 |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | 1 |
| 26 | {"k1":"v1","k2":200} | 1 |
+------+---------------------------------------------------------------+--------------------------------+
19 rows in set (0.03 sec)
mysql> SELECT id, j, jsonb_exists_path(j, '$[2]') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+--------------------------------+
| id | j | jsonb_exists_path(`j`, '$[2]') |
+------+---------------------------------------------------------------+--------------------------------+
| 1 | NULL | NULL |
| 2 | null | 0 |
| 3 | true | 0 |
| 4 | false | 0 |
| 5 | 100 | 0 |
| 6 | 10000 | 0 |
| 7 | 1000000000 | 0 |
| 8 | 1152921504606846976 | 0 |
| 9 | 6.18 | 0 |
| 10 | "abcd" | 0 |
| 11 | {} | 0 |
| 12 | {"k1":"v31","k2":300} | 0 |
| 13 | [] | 0 |
| 14 | [123,456] | 0 |
| 15 | ["abc","def"] | 0 |
| 16 | [null,true,false,100,6.18,"abc"] | 1 |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | 1 |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | 0 |
| 26 | {"k1":"v1","k2":200} | 0 |
+------+---------------------------------------------------------------+--------------------------------+
19 rows in set (0.02 sec)
用jsonb_type获取json内的某个字段的类型
返回json path对应的json字段类型,如果不存在返回NULL
mysql> SELECT id, j, jsonb_type(j, '$') FROM test_jsonb ORDER BY id;
+------+---------------------------------------------------------------+----------------------+
| id | j | jsonb_type(`j`, '$') |
+------+---------------------------------------------------------------+----------------------+
| 1 | NULL | NULL |
| 2 | null | null |
| 3 | true | bool |
| 4 | false | bool |
| 5 | 100 | int |
| 6 | 10000 | int |
| 7 | 1000000000 | int |
| 8 | 1152921504606846976 | bigint |
| 9 | 6.18 | double |
| 10 | "abcd" | string |
| 11 | {} | object |
| 12 | {"k1":"v31","k2":300} | object |
| 13 | [] | array |
| 14 | [123,456] | array |
| 15 | ["abc","def"] | array |
| 16 | [null,true,false,100,6.18,"abc"] | array |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | array |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | object |
| 26 | {"k1":"v1","k2":200} | object |
+------+---------------------------------------------------------------+----------------------+
19 rows in set (0.02 sec)
mysql> select id, j, jsonb_type(j, '$.k1') from test_jsonb order by id;
+------+---------------------------------------------------------------+-------------------------+
| id | j | jsonb_type(`j`, '$.k1') |
+------+---------------------------------------------------------------+-------------------------+
| 1 | NULL | NULL |
| 2 | null | NULL |
| 3 | true | NULL |
| 4 | false | NULL |
| 5 | 100 | NULL |
| 6 | 10000 | NULL |
| 7 | 1000000000 | NULL |
| 8 | 1152921504606846976 | NULL |
| 9 | 6.18 | NULL |
| 10 | "abcd" | NULL |
| 11 | {} | NULL |
| 12 | {"k1":"v31","k2":300} | string |
| 13 | [] | NULL |
| 14 | [123,456] | NULL |
| 15 | ["abc","def"] | NULL |
| 16 | [null,true,false,100,6.18,"abc"] | NULL |
| 17 | [{"k1":"v41","k2":400},1,"a",3.14] | NULL |
| 18 | {"k1":"v31","k2":300,"a1":[{"k1":"v41","k2":400},1,"a",3.14]} | string |
| 26 | {"k1":"v1","k2":200} | string |
+------+---------------------------------------------------------------+-------------------------+
19 rows in set (0.03 sec)
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