我试图只选择包含某个属性的某些行。以下是我正在使用的数据示例：
src_id cand_source ------ ----------- 201609-004d7bgNDFXuIrQPXwsXrOptt2PdTdeXsjV5RJ6_mEQ mcp 201609-004d7bgNDFXuIrQPXwsXrOptt2PdTdeXsjV5RJ6_mEQ mc2 201609-00WmbmuIp3cwAcTNTbrgb9tTVR0AKNf-RvjXcHWPEEQ mc2 201609-00WmbmuIp3cwAcTNTbrgb9tTVR0AKNf-RvjXcHWPEEQ mc2 201609-00WmbmuIp3cwAcTNTbrgb9tTVR0AKNf-RvjXcHWPEEQ mc2 201609-00WmbmuIp3cwAcTNTbrgb9tTVR0AKNf-RvjXcHWPEEQ mc2 201609-00WmbmuIp3cwAcTNTbrgb9tTVR0AKNf-RvjXcHWPEEQ mc2 201609-00WmbmuIp3cwAcTNTbrgb9tTVR0AKNf-RvjXcHWPEEQ mc2 201609-01My_orS795Hmomry3-JiCiBVimarRzRGQ9Cnornp8Q mcp 201609-01My_orS795Hmomry3-JiCiBVimarRzRGQ9Cnornp8Q mcp 201609-01My_orS795Hmomry3-JiCiBVimarRzRGQ9Cnornp8Q mc2 201609-01My_orS795Hmomry3-JiCiBVimarRzRGQ9Cnornp8Q mcp 201609-01My_orS795Hmomry3-JiCiBVimarRzRGQ9Cnornp8Q mc2 201609-01noPFGBCqbH9jUB9MHNqPynjqW8cr24LJY917vSGTs mc2 201609-01noPFGBCqbH9jUB9MHNqPynjqW8cr24LJY917vSGTs mc2 201609-02ISoPEX0VVkQ0ogot49Q-e7K39Zyk2vdN1rB4Q-kl0 mc2 201609-02ISoPEX0VVkQ0ogot49Q-e7K39Zyk2vdN1rB4Q-kl0 mc2 201609-02LVZ8UqAaz7JCp3RAOTiIE7zH2mveiSQPBo6I6dHDc mc2 201609-02LVZ8UqAaz7JCp3RAOTiIE7zH2mveiSQPBo6I6dHDc mc2 201609-03dLH32kaKYVwIj4HiT1tZjCNgqgXiG-fvezX3S9QI4 mc2 201609-03dLH32kaKYVwIj4HiT1tZjCNgqgXiG-fvezX3S9QI4 mc2 201609-0421Jatpsk9T8GOD1M_GvDrnyV4dA41IL5tDeuTxGwU mc2 201609-0421Jatpsk9T8GOD1M_GvDrnyV4dA41IL5tDeuTxGwU mc2 201609-0421Jatpsk9T8GOD1M_GvDrnyV4dA41IL5tDeuTxGwU mc2 201609-0421Jatpsk9T8GOD1M_GvDrnyV4dA41IL5tDeuTxGwU mc2 201609-0421Jatpsk9T8GOD1M_GvDrnyV4dA41IL5tDeuTxGwU mc2 201609-0421Jatpsk9T8GOD1M_GvDrnyV4dA41IL5tDeuTxGwU mc2 201609-0421Jatpsk9T8GOD1M_GvDrnyV4dA41IL5tDeuTxGwU mc2 201609-0421Jatpsk9T8GOD1M_GvDrnyV4dA41IL5tDeuTxGwU mc2 201609-0421Jatpsk9T8GOD1M_GvDrnyV4dA41IL5tDeuTxGwU mc2 201609-04HzM6NBIx_6QN91xzF9_p0RGfAQcRMeEhVFEPFZ8p4 mcp 201609-04HzM6NBIx_6QN91xzF9_p0RGfAQcRMeEhVFEPFZ8p4 mc2 201609-04HzM6NBIx_6QN91xzF9_p0RGfAQcRMeEhVFEPFZ8p4 mc2 201609-04HzM6NBIx_6QN91xzF9_p0RGfAQcRMeEhVFEPFZ8p4 mc2 201609-04HzM6NBIx_6QN91xzF9_p0RGfAQcRMeEhVFEPFZ8p4 mc2 201609-04HzM6NBIx_6QN91xzF9_p0RGfAQcRMeEhVFEPFZ8p4 mc2 201609-04HzM6NBIx_6QN91xzF9_p0RGfAQcRMeEhVFEPFZ8p4 mc2 201609-04HzM6NBIx_6QN91xzF9_p0RGfAQcRMeEhVFEPFZ8p4 mc2 201609-04HzM6NBIx_6QN91xzF9_p0RGfAQcRMeEhVFEPFZ8p4 mc2 201609-04JzR3AMxsfQvAeq1MAgjCtMhcaqt2Z_WNmuUlYLrLM mc2 201609-04JzR3AMxsfQvAeq1MAgjCtMhcaqt2Z_WNmuUlYLrLM mcp
我想要做的只是选择至少有src_id等于cand_source的{{1}}。以下是我尝试过的内容：
mcp然而，这会让我回复SELECT *
FROM schema.table
WHERE src_id IN (
SELECT src_id
FROM schema.table
WHERE batch_id = ?
GROUP BY src_id
HAVING count(cand_source = 'mcp') > 1
)
ORDER BY src_id,
match_score DESC
个没有src_id等于cand_source的群集。
有人指出，我只是过分复杂的事情。这是解决方案：
mcp答案 0 :(得分：1)
如果您只想要源ID，那么您的子查询就是您所需要的。但是，您想要计算匹配值的数量。这是详细的逻辑：
SELECT src_id
FROM schema.table
WHERE batch_id = ?
GROUP BY src_id
HAVING SUM(case when cand_source = 'mcp' then 1 else 0 end) > 1
更简洁的版本是：
HAVING SUM(cand_source = 'mcp'::int) > 1
答案 1 :(得分：1)
如果你只是想要拥有mcp的src_id，那么带有WHERE子句的直接查询就足够了，不需要条件聚合或任何东西。
SELECT DISTINCT
src_id
FROM
Table
WHERE
cand_source = 'mcp'
AND batch_id = ?
如果您希望每个src_id的所有记录至少有一个cand_source，那么您可以将其加入表中以接收所有记录。
SELECT t.*
FROM
Table t
INNER JOIN
(SELECT DISTINCT src_id
FROM Table
WHERE cand_source = 'mcp'
AND batch_id = ? ) d ON t.src_id = d.src_id
AND t.batch_id = ?
或者你可以使用Common Table Expression和令人敬畏的窗口函数来完成它。
WITH cte AS
(
SELECT *, COUNT(CASE WHEN cand_source = 'mcp' THEN cand_source END) OVER (PARTITION BY src_id) as McpCount
FROM
Table
WHERE
batch_id = ?
)
SELECT *
FROM
cte
WHERE
McpCount > 0;