1、查询表结构

show create table data_lake_ods.test

CREATE TABLE spark_catalog.data_lake_ods.test (
`user_number` BIGINT NOT NULL,
`subclazz_number` BIGINT NOT NULL,
`clazz_number` BIGINT,
`clazz_lesson_number` BIGINT NOT NULL,
`lesson_live_property` BIGINT,
`lesson_video_property` BIGINT,
`lesson_live_length` BIGINT,
`lesson_video_length` BIGINT,
`lesson_standard_length` BIGINT,
`lesson_length` BIGINT,
`live_learn_duration` BIGINT,
`video_learn_duration` BIGINT,
`learn_duration` BIGINT,
`is_valid_live_learn` BIGINT,
`is_valid_learn` BIGINT,
`companion_learn_duration` BIGINT,
`learn_combine_duration` BIGINT,
`companion_lesson_length` BIGINT,
`is_should_attend_user` BIGINT,
`is_live_attend_user` BIGINT,
`is_combine_valid_learn_user` BIGINT,
`is_black_user` BIGINT)
USING iceberg
LOCATION '/user/hive/warehouse/data_lake_ods.db/test'
TBLPROPERTIES(
'catalog-database' = 'data_lake_ods',
'catalog-name' = 'spark_catalog',
'catalog-table' = 'test',
'catalog-type' = 'hive',
'connector' = 'iceberg',
'current-snapshot-id' = '5677214384524195741',
'format' = 'iceberg/parquet',
'format-version' = '2',
'identifier-fields' = '[clazz_lesson_number,subclazz_number,user_number]',
'table.drop.base-path.enabled' = 'true',
'uri' = 'thrift://127.0.0.1:7004,******',
'write-parallelism' = '16',
'write.distribution-mode' = 'hash',
'write.merge.mode' = 'merge-on-read',
'write.metadata.delete-after-commit.enabled' = 'true',
'write.metadata.metrics.default' = 'full',
'write.metadata.previous-versions-max' = '100',
'write.update.mode' = 'merge-on-read',
'write.upsert.enabled' = 'true')

2、得到表存储路径后查询最新的metadata.json文件

hdfs dfs -ls /user/hive/warehouse/data_lake_ods.db/test/metadata/
得到最新的文件是:/user/hive/warehouse/data_lake_ods.db/test/metadata/00059-1d8e6694-f873-45a3-9697-ce2762f78c3a.metadata.json

3、查看文件内容

hdfs dfs -cat /user/hive/warehouse/data_lake_ods.db/test/metadata/00059-1d8e6694-f873-45a3-9697-ce2762f78c3a.metadata.json

4、找到"current-snapshot-id" : 5677214384524195741。其实和建表中的id一样

"current-snapshot-id" : 5677214384524195741,
{
"sequence-number" : 59,
"snapshot-id" : 5677214384524195741,
"parent-snapshot-id" : 922737561337808536,
"timestamp-ms" : 1701683779323,
"summary" : {
"operation" : "overwrite",
"flink.operator-id" : "e883208d19e3c34f8aaf2a3168a63337",
"flink.job-id" : "000000001de734af0000000000000000",
"flink.max-committed-checkpoint-id" : "59",
"added-data-files" : "16",
"added-equality-delete-files" : "16",
"added-position-delete-files" : "16",
"added-delete-files" : "32",
"added-records" : "611418",
"added-files-size" : "19072474",
"added-position-deletes" : "245062",
"added-equality-deletes" : "366356",
"changed-partition-count" : "1",
"total-records" : "1084028212",
"total-files-size" : "41957333041",
"total-data-files" : "944",
"total-delete-files" : "1680",
"total-position-deletes" : "10749681",
"total-equality-deletes" : "1073278531"
},
"manifest-list" : "/user/hive/warehouse/data_lake_ods.db/test/metadata/snap-5677214384524195741-1-644d4e57-0953-40c0-915d-faf7dd8a3ab2.avro",
"schema-id" : 0
}

5、得到manifest-list文件路径,下载到本地分析

hadoop fs -get /user/hive/warehouse/data_lake_ods.db/test/metadata/snap-5677214384524195741-1-644d4e57-0953-40c0-915d-faf7dd8a3ab2.avro ~/test/iceberg

6、查看avro文件内容

java -jar ./avro-tools-1.8.1.jar tojson ./snap-5677214384524195741-1-644d4e57-0953-40c0-915d-faf7dd8a3ab2.avro | less |grep '5677214384524195741'
内容如下:
{"manifest_path":"/user/hive/warehouse/data_lake_ods.db/test/metadata/644d4e57-0953-40c0-915d-faf7dd8a3ab2-m0.avro","manifest_length":12233,"partition_spec_id":0,"content":0,"sequence_number":59,"min_sequence_number":59,"added_snapshot_id":567721438452419574,"added_data_files_count":16,"existing_data_files_count":0,"deleted_data_files_count":0,"added_rows_count":611418,"existing_rows_count":0,"deleted_rows_count":0,"partitions":{"array":[]}}
{"manifest_path":"/user/hive/warehouse/data_lake_ods.db/test/metadata/644d4e57-0953-40c0-915d-faf7dd8a3ab2-m1.avro","manifest_length":10241,"partition_spec_id":0,"content":1,"sequence_number":59,"min_sequence_number":59,"added_snapshot_id":567721438452419574,"added_data_files_count":32,"existing_data_files_count":0,"deleted_data_files_count":0,"added_rows_count":611418,"existing_rows_count":0,"deleted_rows_count":0,"partitions":{"array":[]}}

7、查询其中一个文件内容

hadoop fs -get /user/hive/warehouse/data_lake_ods.db/test/metadata/644d4e57-0953-40c0-915d-faf7dd8a3ab2-m0.avro ~/test/iceberg
java -jar ./avro-tools-1.8.1.jar tojson ./644d4e57-0953-40c0-915d-faf7dd8a3ab2-m0.avro | less
数据样例:
{"status":1,"snapshot_id":{"long":5677214384524195741},"sequence_number":null,"file_sequence_number":null,"data_file":{"content":0,"file_path":"/user/hive/warehouse/data_lake_ods.db/test/data/00009-0-a2f03c5f-eec9-4a15-bafe-9b360af4fde5-00162.parquet","file_format":"PARQUET","partition":{},"record_count":38138,"file_size_in_bytes":899517,"column_sizes":{"array":[{"key":1,"value":178768},{"key":2,"value":90942},{"key":3,"value":68674},{"key":4,"value":95511},{"key":5,"value":9520},{"key":6,"value":6952},{"key":7,"value":47567},{"key":8,"value":42993},{"key":9,"value":29052},{"key":10,"value":39705},{"key":11,"value":59926},{"key":12,"value":40560},{"key":13,"value":67603},{"key":14,"value":8252},{"key":15,"value":8365},{"key":16,"value":7477},{"key":17,"value":67708},{"key":18,"value":6603},{"key":19,"value":5850},{"key":20,"value":5150},{"key":21,"value":5096},{"key":22,"value":246}]},"value_counts":{"array":[{"key":1,"value":38138},{"key":2,"value":38138},{"key":3,"value":38138},{"key":4,"value":38138},{"key":5,"value":38138},{"key":6,"value":38138},{"key":7,"value":38138},{"key":8,"value":38138},{"key":9,"value":38138},{"key":10,"value":38138},{"key":11,"value":38138},{"key":12,"value":38138},{"key":13,"value":38138},{"key":14,"value":38138},{"key":15,"value":38138},{"key":16,"value":38138},{"key":17,"value":38138},{"key":18,"value":38138},{"key":19,"value":38138},{"key":20,"value":38138},{"key":21,"value":38138},{"key":22,"value":38138}]},"null_value_counts":{"array":[{"key":1,"value":0},{"key":2,"value":0},{"key":3,"value":0},{"key":4,"value":0},{"key":5,"value":11091},{"key":6,"value":11092},{"key":7,"value":11091},{"key":8,"value":11092},{"key":9,"value":11091},{"key":10,"value":11091},{"key":11,"value":11091},{"key":12,"value":11091},{"key":13,"value":11091},{"key":14,"value":11091},{"key":15,"value":11091},{"key":16,"value":11091},{"key":17,"value":11091},{"key":18,"value":11091},{"key":19,"value":0},{"key":20,"value":0},{"key":21,"value":0},{"key":22,"value":0}]},"nan_value_counts":{"array":[]},"lower_bounds":{"array":[{"key":1,"value":"'\u0006\u0002\u0000\u0000\u0000\u0000\u0000"},{"key":2,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":3,"value":"\u0000\u0000<U+008D><Ú\u000B\t\u0000"},{"key":4,"value":",\u0000ß<Ú\u000B\t\u0000"},{"key":5,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":6,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":7,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":8,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":9,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":10,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":11,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":12,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":13,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":14,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":15,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":16,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":17,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":18,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":19,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":20,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":21,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":22,"value":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000"}]},"upper_bounds":{"array":[{"key":1,"value":"C<U+0095>\u0014\u0006<U+008E>å\u0000\u0000"},{"key":2,"value":"<U+0080>\u0004 <U+0084>´ÇW\u0000"},{"key":3,"value":"\u0000à`t_º{\u0005"},{"key":4,"value":"\u0000°ÃZ\"<U+0097>|\u0005"},{"key":5,"value":"\u0003\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":6,"value":"\u0003\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":7,"value":"<U+0081>L\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":8,"value":"zL\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":9,"value":"`T\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":10,"value":"$4\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":11,"value":"18\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":12,"value":"£8\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":13,"value":"~:\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":14,"value":"\u0001\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":15,"value":"\u0001\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":16,"value":"<U+0091>\u001A\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":17,"value":"~:\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":18,"value":"B\u001B\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":19,"value":"\u0002\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":20,"value":"\u0001\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":21,"value":"\u0001\u0000\u0000\u0000\u0000\u0000\u0000\u0000"},{"key":22,"value":"\u0001\u0000\u0000\u0000\u0000\u0000\u0000\u0000"}]},"key_metadata":null,"split_offsets":{"array":[4]},"equality_ids":null,"sort_order_id":{"int":0}}}

8、根据第六步得到的文件路径查看文件内容

(1)查topN数据

hadoop jar ./parquet-tools-1.11.0.jar head -n 10  /user/hive/warehouse/data_lake_ods.db/test/data/00009-0-a2f03c5f-eec9-4a15-bafe-9b360af4fde5-00162.parquet
数据样例:

user_number = 19100811
subclazz_number = 22388336842768640
clazz_number = 10995946454325888
clazz_lesson_number = 10995946455505548
lesson_live_property = 0
lesson_video_property = 0
lesson_live_length = 6091
lesson_video_length = 0
lesson_standard_length = 7200
lesson_length = 6091
live_learn_duration = 476
video_learn_duration = 0
learn_duration = 476
is_valid_live_learn = 0
is_valid_learn = 0
companion_learn_duration = 0
learn_combine_duration = 476
companion_lesson_length = 0
is_should_attend_user = 0
is_live_attend_user = 1
is_combine_valid_learn_user = 0
is_black_user = 0

(2)查元数据,表格式

hadoop jar ./parquet-tools-1.11.0.jar schema /user/hive/warehouse/data_lake_ods.db/test/data/00009-0-a2f03c5f-eec9-4a15-bafe-9b360af4fde5-00162.parquet
message table {
required int64 user_number = 1;
required int64 subclazz_number = 2;
optional int64 clazz_number = 3;
required int64 clazz_lesson_number = 4;
optional int64 lesson_live_property = 5;
optional int64 lesson_video_property = 6;
optional int64 lesson_live_length = 7;
optional int64 lesson_video_length = 8;
optional int64 lesson_standard_length = 9;
optional int64 lesson_length = 10;
optional int64 live_learn_duration = 11;
optional int64 video_learn_duration = 12;
optional int64 learn_duration = 13;
optional int64 is_valid_live_learn = 14;
optional int64 is_valid_learn = 15;
optional int64 companion_learn_duration = 16;
optional int64 learn_combine_duration = 17;
optional int64 companion_lesson_length = 18;
optional int64 is_should_attend_user = 19;
optional int64 is_live_attend_user = 20;
optional int64 is_combine_valid_learn_user = 21;
optional int64 is_black_user = 22;
}

(3)查看meta信息
hadoop jar /home/hadoop/test/iceberg/parquet-tools-1.11.0.jar meta /user/hive/warehouse/data_lake_ods.db/test/data/00009-0-a2f03c5f-eec9-4a15-bafe-9b360af4fde5-00162.parquet

file:                        /user/hive/warehouse/data_lake_ods.db/test/data/00009-0-a2f03c5f-eec9-4a15-bafe-9b360af4fde5-00162.parquet
creator: parquet-mr version 1.13.1 (build db4183109d5b734ec5930d870cdae161e408ddba)
extra: iceberg.schema = {"type":"struct","schema-id":0,"identifier-field-ids":[1,2,4],"fields":[{"id":1,"name":"user_number","required":true,"type":"long"},{"id":2,"name":"subclazz_number","required":true,"type":"long"},{"id":3,"name":"clazz_number","required":false,"type":"long"},{"id":4,"name":"clazz_lesson_number","required":true,"type":"long"},{"id":5,"name":"lesson_live_property","required":false,"type":"long"},{"id":6,"name":"lesson_video_property","required":false,"type":"long"},{"id":7,"name":"lesson_live_length","required":false,"type":"long"},{"id":8,"name":"lesson_video_length","required":false,"type":"long"},{"id":9,"name":"lesson_standard_length","required":false,"type":"long"},{"id":10,"name":"lesson_length","required":false,"type":"long"},{"id":11,"name":"live_learn_duration","required":false,"type":"long"},{"id":12,"name":"video_learn_duration","required":false,"type":"long"},{"id":13,"name":"learn_duration","required":false,"type":"long"},{"id":14,"name":"is_valid_live_learn","required":false,"type":"long"},{"id":15,"name":"is_valid_learn","required":false,"type":"long"},{"id":16,"name":"companion_learn_duration","required":false,"type":"long"},{"id":17,"name":"learn_combine_duration","required":false,"type":"long"},{"id":18,"name":"companion_lesson_length","required":false,"type":"long"},{"id":19,"name":"is_should_attend_user","required":false,"type":"long"},{"id":20,"name":"is_live_attend_user","required":false,"type":"long"},{"id":21,"name":"is_combine_valid_learn_user","required":false,"type":"long"},{"id":22,"name":"is_black_user","required":false,"type":"long"}]} file schema: table
--------------------------------------------------------------------------------
user_number: REQUIRED INT64 R:0 D:0
subclazz_number: REQUIRED INT64 R:0 D:0
clazz_number: OPTIONAL INT64 R:0 D:1
clazz_lesson_number: REQUIRED INT64 R:0 D:0
lesson_live_property: OPTIONAL INT64 R:0 D:1
lesson_video_property: OPTIONAL INT64 R:0 D:1
lesson_live_length: OPTIONAL INT64 R:0 D:1
lesson_video_length: OPTIONAL INT64 R:0 D:1
lesson_standard_length: OPTIONAL INT64 R:0 D:1
lesson_length: OPTIONAL INT64 R:0 D:1
live_learn_duration: OPTIONAL INT64 R:0 D:1
video_learn_duration: OPTIONAL INT64 R:0 D:1
learn_duration: OPTIONAL INT64 R:0 D:1
is_valid_live_learn: OPTIONAL INT64 R:0 D:1
is_valid_learn: OPTIONAL INT64 R:0 D:1
companion_learn_duration: OPTIONAL INT64 R:0 D:1
learn_combine_duration: OPTIONAL INT64 R:0 D:1
companion_lesson_length: OPTIONAL INT64 R:0 D:1
is_should_attend_user: OPTIONAL INT64 R:0 D:1
is_live_attend_user: OPTIONAL INT64 R:0 D:1
is_combine_valid_learn_user: OPTIONAL INT64 R:0 D:1
is_black_user: OPTIONAL INT64 R:0 D:1 row group 1: RC:38138 TS:1269627 OFFSET:4
--------------------------------------------------------------------------------
user_number: INT64 GZIP DO:4 FPO:112797 SZ:178768/238215/1.33 VC:38138 ENC:BIT_PACKED,PLAIN_DICTIONARY ST:[min: 132647, max: 252398150128963, num_nulls: 0]
subclazz_number: INT64 GZIP DO:178772 FPO:216044 SZ:90942/116042/1.28 VC:38138 ENC:BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 24707901098558592, num_nulls: 0]
clazz_number: INT64 GZIP DO:269714 FPO:287587 SZ:68674/79130/1.15 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 2546306737045504, max: 395114311462215680, num_nulls: 0]
clazz_lesson_number: INT64 GZIP DO:338388 FPO:374110 SZ:95511/115465/1.21 VC:38138 ENC:BIT_PACKED,PLAIN_DICTIONARY ST:[min: 2546306742419500, max: 395357041109217280, num_nulls: 0]
lesson_live_property: INT64 GZIP DO:433899 FPO:433948 SZ:9520/11698/1.23 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 3, num_nulls: 11091]
lesson_video_property: INT64 GZIP DO:443419 FPO:443469 SZ:6952/9243/1.33 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 3, num_nulls: 11092]
lesson_live_length: INT64 GZIP DO:450371 FPO:456873 SZ:47567/64261/1.35 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 19585, num_nulls: 11091]
lesson_video_length: INT64 GZIP DO:497938 FPO:505857 SZ:42993/70204/1.63 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 19578, num_nulls: 11092]
lesson_standard_length: INT64 GZIP DO:540931 FPO:543782 SZ:29052/49418/1.70 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 21600, num_nulls: 11091]
lesson_length: INT64 GZIP DO:569983 FPO:575653 SZ:39705/61757/1.56 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 13348, num_nulls: 11091]
live_learn_duration: INT64 GZIP DO:609688 FPO:625930 SZ:59926/99798/1.67 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 14385, num_nulls: 11091]
video_learn_duration: INT64 GZIP DO:669614 FPO:680817 SZ:40560/80714/1.99 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 14499, num_nulls: 11091]
learn_duration: INT64 GZIP DO:710174 FPO:728644 SZ:67603/106804/1.58 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 14974, num_nulls: 11091]
is_valid_live_learn: INT64 GZIP DO:777777 FPO:777819 SZ:8252/8680/1.05 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 1, num_nulls: 11091]
is_valid_learn: INT64 GZIP DO:786029 FPO:786071 SZ:8365/8705/1.04 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 1, num_nulls: 11091]
companion_learn_duration: INT64 GZIP DO:794394 FPO:795351 SZ:7477/12507/1.67 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 6801, num_nulls: 11091]
learn_combine_duration: INT64 GZIP DO:801871 FPO:820446 SZ:67708/107108/1.58 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 14974, num_nulls: 11091]
companion_lesson_length: INT64 GZIP DO:869579 FPO:869883 SZ:6603/9775/1.48 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 6978, num_nulls: 11091]
is_should_attend_user: INT64 GZIP DO:876182 FPO:876227 SZ:5850/9754/1.67 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 2, num_nulls: 0]
is_live_attend_user: INT64 GZIP DO:882032 FPO:882077 SZ:5150/5094/0.99 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 1, num_nulls: 0]
is_combine_valid_learn_user: INT64 GZIP DO:887182 FPO:887227 SZ:5096/5042/0.99 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 1, num_nulls: 0]
is_black_user: INT64 GZIP DO:892278 FPO:892323 SZ:246/213/0.87 VC:38138 ENC:RLE,BIT_PACKED,PLAIN_DICTIONARY ST:[min: 0, max: 1, num_nulls: 0]

spark-sql查询Iceberg时处理流程的更多相关文章

  1. 大数据技术之_19_Spark学习_03_Spark SQL 应用解析 + Spark SQL 概述、解析 、数据源、实战 + 执行 Spark SQL 查询 + JDBC/ODBC 服务器

    第1章 Spark SQL 概述1.1 什么是 Spark SQL1.2 RDD vs DataFrames vs DataSet1.2.1 RDD1.2.2 DataFrame1.2.3 DataS ...

  2. 【原创】大叔经验分享(23)spark sql插入表时的文件个数研究

    spark sql执行insert overwrite table时,写到新表或者新分区的文件个数,有可能是200个,也有可能是任意个,为什么会有这种差别? 首先看一下spark sql执行inser ...

  3. spark sql插入表时的文件个数研究

    spark sql执行insert overwrite table时,写到新表或者新分区的文件个数,有可能是200个,也有可能是任意个,为什么会有这种差别? 首先看一下spark sql执行inser ...

  4. sql查询语句时怎么把几个字段拼接成一个字段

    sql查询语句时怎么把几个字段拼接成一个字段SELECT CAST(COLUMN1 AS VARCHAR(10)) + '-' + CAST(COLUMN2 AS VARCHAR(10) ...) a ...

  5. Spark SQL源代码分析之核心流程

    /** Spark SQL源代码分析系列文章*/ 自从去年Spark Submit 2013 Michael Armbrust分享了他的Catalyst,到至今1年多了,Spark SQL的贡献者从几 ...

  6. MySQL数据库详解(一)执行SQL查询语句时,其底层到底经历了什么?

    一条SQL查询语句是如何执行的? 前言 ​ 大家好,我是WZY,今天我们学习下MySQL的基础框架,看一件事千万不要直接陷入细节里,你应该先鸟瞰其全貌,这样能够帮助你从高维度理解问题.同样,对于MyS ...

  7. 2. 执行Spark SQL查询

    2.1 命令行查询流程 打开Spark shell 例子:查询大于21岁的用户 创建如下JSON文件,注意JSON的格式: {"name":"Michael"} ...

  8. Hibernate通过SQL查询常量时只能返回第一个字符的解决方法

    在Hibernate中如果通过 [java] view plaincopy session.createSQLQuery("select '合计' as name from dual&quo ...

  9. spark sql 查询hive表并写入到PG中

    import java.sql.DriverManager import java.util.Properties import com.zhaopin.tools.{DateUtils, TextU ...

  10. Databricks 第11篇:Spark SQL 查询(行转列、列转行、Lateral View、排序)

    本文分享在Azure Databricks中如何实现行转列和列转行. 一,行转列 在分组中,把每个分组中的某一列的数据连接在一起: collect_list:把一个分组中的列合成为数组,数据不去重,格 ...

随机推荐

  1. Windows下驱动安装

    推荐使用金山毒霸中的电脑医生进行驱动或DLL文件的扫描,查找并下载 dll文件下载地址:  https://www.wenjian.net/ 可以进行下载,告诉该文件的放置路径 其他:

  2. Echarts 颜色管理

    1.Echarts的颜色设计 Echarts的颜色的设置分为两种:色盘和具体颜色 色盘适合做全局设置,因为他里面有多个颜色,通俗的说色盘就是颜色预设值列表,色盘统一使用color属性进行配置. 而具体 ...

  3. ant 组件全局设置中文 vue

    //引入中文组件import zhCN from 'ant-design-vue/es/locale/zh_CN';//定义 const  locale = zhCN   //包裹根组件 <a- ...

  4. jumpserver 工单系统 二次开发工单管理并开源代码

    介绍 JumpServer 是广受欢迎的开源堡垒机,是符合 4A 规范的专业运维安全审计系统.JumpServer 帮助企业以更安全的方式管控和登录所有类型的资产,实现事前授权.事中监察.事后审计,满 ...

  5. 渗透测试-前端加密分析之AES

    前言 本文是高级前端加解密与验签实战的第3篇文章,本系列文章实验靶场为Yakit里自带的Vulinbox靶场,本文讲述的是绕过前端 AES(CBC) 和 AES(ECB) 加密. 因为编写Yakit热 ...

  6. 对 .NET 开发者来说,Azure AD 改名为 Microsoft Entra ID 意味着什么?

    对 .NET 开发者来说,Azure AD 改名为 Microsoft Entra ID 意味着什么? 原文地址:https://devblogs.microsoft.com/dotnet/azure ...

  7. HttpClientFactory in ASP.NET Core 2.1 Part 2:定义命名和类型化的客户端

    HttpClientFactory in ASP.NET Core 2.1 Part 2:定义命名和类型化的客户端 原文地址:https://www.stevejgordon.co.uk/httpcl ...

  8. 2024年1月Java项目开发指南8:统一数据返回格式

    有时候返回一个字符串,有时候返回一串数字代码,有时候返回一个对象-- 不过怎么说,我们返回的内容往往具有三个 1.消息代码 code 2.消息内容 msg 3.数据内容 data 接下来,我们要编写一 ...

  9. swagger 文件上传以及requestbody参数传递

    swagger用来做普通的API测试很方便,在实际开发过程中,经常会有文件上传,或者通过reuestbody传递数据等方式. 这个时候swagger的配置就有一些特殊了 . swagger reque ...

  10. Qt编写物联网管理平台40-类型种类

    一.前言 为了增强本系统的拓展性,做成通用的物联网管理平台,特意将控制器主设备类型.探测器子设备类型.对应种类符号等信息,全部做成表格可自定义添加和修改,这样在控制器信息表和探测器信息表管理的时候,可 ...