我需要检查(从同一个表中)两个事件之间是否存在基于日期-时间的关联。
一组数据将包含某些事件的结束日期-时间,另一组数据将包含其他事件的开始日期-时间。
如果第一个事件在第二个事件之前完成,那么我想把它们联系起来。
到目前为止,我有:
SELECT name as name_A, date-time as end_DTS, id as id_A
FROM tableA WHERE criteria = 1
SELECT name as name_B, date-time as start_DTS, id as id_B
FROM tableA WHERE criteria = 2
然后我加入他们:
SELECT name_A, name_B, id_A, id_B,
if(start_DTS > end_DTS,'VALID','') as validation_check
FROM tableA
LEFT JOIN tableB ON name_A = name_B
然后,我可以根据validation_check字段运行一个带有SELECT嵌套的UPDATE查询吗?
如果您正在从一个复杂的查询进行更新。最好的方法是从查询创建临时表,然后使用临时表作为一个查询进行更新。
DROP TABLE IF EXISTS cash_sales_sums;
CREATE TEMPORARY TABLE cash_sales_sums as
SELECT tbl_cash_sales_documents.batch_key, COUNT(DISTINCT tbl_cash_sales_documents.cash_sale_number) no_of_docs,
SUM(tbl_cash_sales_documents.paid_amount) paid_amount, SUM(A.amount - tbl_cash_sales_documents.bonus_amount - tbl_cash_sales_documents.discount_given) amount,
SUM(A.recs) no_of_entries FROM
tbl_cash_sales_documents
RIGHT JOIN(
SELECT
SUM(
tbl_cash_sales_transactions.amount
)amount,
tbl_cash_sales_transactions.cash_sale_document_id,
COUNT(transaction_id)recs
FROM
tbl_cash_sales_transactions
GROUP BY
tbl_cash_sales_transactions.cash_sale_document_id
)A ON A.cash_sale_document_id = tbl_cash_sales_documents.cash_sale_id
GROUP BY
tbl_cash_sales_documents.batch_key
ORDER BY batch_key;
UPDATE tbl_cash_sales_batches SET control_totals = (SELECT amount FROM cash_sales_sums WHERE cash_sales_sums.batch_key = tbl_cash_sales_batches.batch_key LIMIT 1),
expected_number_of_documents = (SELECT no_of_docs FROM cash_sales_sums WHERE cash_sales_sums.batch_key = tbl_cash_sales_batches.batch_key),
computer_number_of_documents = expected_number_of_documents, computer_total_amount = control_totals
WHERE batch_key IN (SELECT batch_key FROM cash_sales_sums);
如果您正在从一个复杂的查询进行更新。最好的方法是从查询创建临时表,然后使用临时表作为一个查询进行更新。
DROP TABLE IF EXISTS cash_sales_sums;
CREATE TEMPORARY TABLE cash_sales_sums as
SELECT tbl_cash_sales_documents.batch_key, COUNT(DISTINCT tbl_cash_sales_documents.cash_sale_number) no_of_docs,
SUM(tbl_cash_sales_documents.paid_amount) paid_amount, SUM(A.amount - tbl_cash_sales_documents.bonus_amount - tbl_cash_sales_documents.discount_given) amount,
SUM(A.recs) no_of_entries FROM
tbl_cash_sales_documents
RIGHT JOIN(
SELECT
SUM(
tbl_cash_sales_transactions.amount
)amount,
tbl_cash_sales_transactions.cash_sale_document_id,
COUNT(transaction_id)recs
FROM
tbl_cash_sales_transactions
GROUP BY
tbl_cash_sales_transactions.cash_sale_document_id
)A ON A.cash_sale_document_id = tbl_cash_sales_documents.cash_sale_id
GROUP BY
tbl_cash_sales_documents.batch_key
ORDER BY batch_key;
UPDATE tbl_cash_sales_batches SET control_totals = (SELECT amount FROM cash_sales_sums WHERE cash_sales_sums.batch_key = tbl_cash_sales_batches.batch_key LIMIT 1),
expected_number_of_documents = (SELECT no_of_docs FROM cash_sales_sums WHERE cash_sales_sums.batch_key = tbl_cash_sales_batches.batch_key),
computer_number_of_documents = expected_number_of_documents, computer_total_amount = control_totals
WHERE batch_key IN (SELECT batch_key FROM cash_sales_sums);