greatest-n-per-group
Select parent based on attribute of most recent child element
I\'m writing a simple membership application. I have two models, 开发者_StackOverflow社区Member and Membership.[详细]
2023-04-04 04:59 分类:问答How to join two MySQL tables grouped depending on a max() value
while implementing an inline search function for our local file archive I\'ve come up with a serious problem I have found no answer for. We have two tables:[详细]
2023-04-03 08:49 分类:问答"limit" clause on joining?
table1: id , otherColumn, otherColumn2 ... ta开发者_JS百科ble2: id, table1_id, someOtherColumns... I.E. one to many relationships[详细]
2023-04-03 07:23 分类:问答MySql SELECT with GROUP or SUBQUERY with temporary tables? Then ordered TWICE ? How?
Title of question is my thoughts of the solution to the following problem but of course i do not want to limit your answers to that.[详细]
2023-04-02 08:51 分类:问答In mongo, how do I use map reduce to get a group by ordered by most recent
the map reduce examples I see use aggregation functions like count, but what 开发者_StackOverflowis the best way to get say the top 3 items in each category using map reduce.[详细]
2023-04-02 07:55 分类:问答SQL to join the first record in a custom sort order
Sometimes I want to join a record that I can easily identify as \"sort by this and that and pick the first record\". I wonder what the best practice here.[详细]
2023-04-02 07:18 分类:问答Get top two records for each product
I have a table with three fields as below, each product has multiple records. I\'m wondering how can I fetch top 2 for each product? I sorted my records by time field already.[详细]
2023-04-02 02:11 分类:问答Order within group by?
In my system, I have clients. Clients have programs. I want to display a list of clients, showing their most recent active (if it exists) program.[详细]
2023-04-01 09:22 分类:问答problematic sql server query
I have the following query which is running slow: WITH AcdTran AS (select SequenceNo, ReqID, PolNumber, transaction_id,[详细]
2023-04-01 01:46 分类:问答How can I get a single result from a related table in SQL?
I have the following SQL query: SELECT gallery.id, gallery.thumbnail_big, products.id, products.title,[详细]
2023-03-31 20:57 分类:问答