接上篇文章 【kafka KSQL】游戏日志统计分析(2),本文主要通过实例展示KSQL的连接查询功能。
创建另一个topic
bin/kafka-topics --create --zookeeper localhost:2181 --replication-factor 1 --partitions 4 --topic propnew-normalized
往新topic中写入数据
bin/kafka-console-producer --broker-list localhost:9092 --topic propnew-normalized
>
{"user__name":"lzb", "prop__id":"id1"}
从prop-normalized主题创建Stream
CREATE STREAM PROP_USE_EVENT \
(user__name VARCHAR, \
prop__id VARCHAR ) \
WITH (KAFKA_TOPIC='propnew-normalized', \
VALUE_FORMAT='json');
重新设置ROWKEY为user__name
CREATE STREAM PROP_USE_EVENT_REKEY AS \
SELECT * FROM PROP_USE_EVENT \
PARTITION BY user__name;
查询完成3局对局且没有使用过道具的所有玩家
- 查询出所有玩家的对局情况,并创建表
USER_SCORE_TABLE
(前面已经创建过了):
CREATE TABLE USER_SCORE_TABLE AS \
SELECT username, COUNT(*) AS game_count, SUM(delta) AS delta_sum, SUM(tax) AS tax_sum \
FROM USER_SCORE_EVENT_REKEY \
WHERE reason = 'game' \
GROUP BY username;
- 查询出所有玩家的道具使用情况,并创建表
USER_PROP_TABLE
:
CREATE TABLE USER_PROP_TABLE AS \
SELECT user__name, COUNT(*) AS use_count \
FROM PROP_USE_EVENT_REKEY \
GROUP BY user__name;
- 使用LEFT JOIN进行左关联,并以此创建一个新的TABLE:
CREATE TABLE USER_SCORE_AND_PROP AS \
SELECT s.username AS username, s.game_count, s.tax_sum, s.delta_sum, p.use_count \
FROM USER_SCORE_TABLE s \
LEFT JOIN USER_PROP_TABLE p \
ON s.username = p.user__name;
- 查询对局数大于等于3,且没有使用过道具的玩家:
SELECT username FROM USER_SCORE_AND_PROP \
WHERE game_count >= 3 AND use_count IS NULL;
- 查询对局数大于等于3,且使用道具次数大于等于2的玩家:
SELECT username FROM USER_SCORE_AND_PROP \
WHERE game_count >= 3 AND use_count >= 2;
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