SELECT DISTINCT ( A.DATA_TYPE ) AS DATA_TYPE, A.DATA_VALUE AS TSL, IFNULL(( SELECT B.DATA_VALUE FROM YXDDZH_MIDDLE.GZ_SCREEN_JGSY_SDHJ_SPFW_CITY_AREA_DATA B WHERE B.IS_DELETED = 0 AND B.DATA_DIMENSION = '期末' AND B.LEVEL = 2 AND B.DATA_NAME = '举报' AND B.DATA_AREA = '市级' AND B.DATA_TYPE = A.DATA_TYPE AND B.DATA_TIME = ( SELECT MAX( DATA_TIME ) FROM YXDDZH_MIDDLE.GZ_SCREEN_JGSY_SDHJ_SPFW_CITY_AREA_DATA WHERE IS_DELETED = 0 AND DATA_DIMENSION = '期末' AND DATA_NAME = '举报' AND LEVEL = 2 AND DATA_AREA = '市级' ) ), 0 ) AS JBL, CURRENT_ID FROM YXDDZH_MIDDLE.GZ_SCREEN_JGSY_SDHJ_SPFW_CITY_AREA_DATA A WHERE A.IS_DELETED = 0 AND A.DATA_DIMENSION = '期末' AND A.LEVEL = 2 AND A.DATA_NAME = '投诉' AND A.DATA_AREA = '市级' AND A.DATA_TIME = ( SELECT MAX( DATA_TIME ) FROM YXDDZH_MIDDLE.GZ_SCREEN_JGSY_SDHJ_SPFW_CITY_AREA_DATA WHERE IS_DELETED = 0 AND DATA_DIMENSION = '期末' AND DATA_NAME = '投诉' AND LEVEL = 2 AND DATA_AREA = '市级')这个sql 优化
时间: 2023-10-15 17:07:03 浏览: 171
对于这个SQL查询语句的优化,可以考虑以下几点:
1. 使用JOIN语句代替子查询:将子查询转换为JOIN语句,可以提高查询性能。
2. 添加适当的索引:根据查询条件和连接条件,为相关表添加合适的索引,以加快查询速度。
3. 减少重复的条件判断:在子查询和主查询中,有一些条件判断是重复的,可以将它们提取出来,避免重复计算。
4. 使用表别名:为表和字段使用简短的别名,提高查询语句的可读性。
下面是对原始SQL查询语句进行优化的示例:
SELECT DISTINCT
A.DATA_TYPE AS DATA_TYPE,
A.DATA_VALUE AS TSL,
IFNULL(B.DATA_VALUE, 0) AS JBL,
A.CURRENT_ID
FROM
YXDDZH_MIDDLE.GZ_SCREEN_JGSY_SDHJ_SPFW_CITY_AREA_DATA A
LEFT JOIN
(
SELECT
DATA_TYPE, DATA_VALUE
FROM
YXDDZH_MIDDLE.GZ_SCREEN_JGSY_SDHJ_SPFW_CITY_AREA_DATA
WHERE
IS_DELETED = 0
AND DATA_DIMENSION = '期末'
AND DATA_NAME = '举报'
AND LEVEL = 2
AND DATA_AREA = '市级'
AND DATA_TIME = (
SELECT MAX(DATA_TIME)
FROM YXDDZH_MIDDLE.GZ_SCREEN_JGSY_SDHJ_SPFW_CITY_AREA_DATA
WHERE
IS_DELETED = 0
AND DATA_DIMENSION = '期末'
AND DATA_NAME = '举报'
AND LEVEL = 2
AND DATA_AREA = '市级'
)
) B ON A.DATA_TYPE = B.DATA_TYPE
WHERE
A.IS_DELETED = 0
AND A.DATA_DIMENSION = '期末'
AND A.LEVEL = 2
AND A.DATA_NAME = '投诉'
AND A.DATA_AREA = '市级'
AND A.DATA_TIME = (
SELECT MAX(DATA_TIME)
FROM YXDDZH_MIDDLE.GZ_SCREEN_JGSY_SDHJ_SPFW_CITY_AREA_DATA
WHERE
IS_DELETED = 0
AND DATA_DIMENSION = '期末'
AND DATA_NAME = '投诉'
AND LEVEL = 2
AND DATA_AREA = '市级'
);
请注意,具体的优化策略可能需要根据实际情况进行调整和测试,以达到最佳的查询性能。
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