left-join

问题 could you please help me out with this: I have a dataframe ( df1 ) that has index of all articles published in the website's CMS. There's a column for current URL and a column of original URLs in case they were changed after publication (column name Origin ): URL Origin ArticleID Author Category Cost https://example.com/article1 https://example.com/article 001 AuthorName Politics 120 USD https://example.com/article2 https://example.com/article2 002 AuthorName Finance 68 USD Next I have an

问题 I have a table TBL_POST used to store blog posts. A post can be assigned to multiple categories, there is a column, cat_id that stores category ID's in comma separated pattern like 2,4,6 . I want to use FIND_IN_SET() method in this line ->leftJoin(TBL_CAT.' as c', 'p.cat_id', '=', 'c.id') to show the associated category names. How can I do that? public static function getPostWithJoin($status="") { $query = DB::table(TBL_POST .' as p') ->select('p.id','p.post_title','p.post_status','u.name as

问题 I have a table TBL_POST used to store blog posts. A post can be assigned to multiple categories, there is a column, cat_id that stores category ID's in comma separated pattern like 2,4,6 . I want to use FIND_IN_SET() method in this line ->leftJoin(TBL_CAT.' as c', 'p.cat_id', '=', 'c.id') to show the associated category names. How can I do that? public static function getPostWithJoin($status="") { $query = DB::table(TBL_POST .' as p') ->select('p.id','p.post_title','p.post_status','u.name as

问题 I'm having trouble wrapping my head around using a string function such as STARTS_WITH or an operator such as LIKE in a LEFT JOIN ON where the parameters of either come from both tables in the join. Rather than try to explain the abstracts, I've distilled a small example ... Let's consider a table called fuzzylog that has a key field fullname that I want to canonicalize by joining to a names table that has the same column. The key field in fuzzylog may be a bit messy or free-form so a direct

问题 I'm having trouble wrapping my head around using a string function such as STARTS_WITH or an operator such as LIKE in a LEFT JOIN ON where the parameters of either come from both tables in the join. Rather than try to explain the abstracts, I've distilled a small example ... Let's consider a table called fuzzylog that has a key field fullname that I want to canonicalize by joining to a names table that has the same column. The key field in fuzzylog may be a bit messy or free-form so a direct

问题 I want to get data if orgid = 2 or if there is no row at all for the uid . orgid is an integer . The closest thing I could think of is to do IS NULL but I'm not getting data for the uid that doesn't have an orgid row. Any idea? select u.uid,u.fname,u.lname from u inner join u_org on u.uid = u_org.uid inner join login on u.uid = login.uid where u_org.orgid=2 or u_org.orgid is NULL and login.access != 4; Basically the OR is if u_org.orgid row doesn't exist. 回答1: If there is "no row at all for

问题 This topic is related to my previews one Join two tables with all records I'm tryng now to join 3 or more tables in my Laravel controller code, and view them in one Datatable. table1 +--------------------+---------+ | recordtime | tempout | +--------------------+---------+ | 4.12.2020 10:00:00 | 1.1 | | 4.12.2020 10:30:00 | 1.2 | | 4.12.2020 11:00:00 | 1.3 | | 4.12.2020 11:30:00 | 1.4 | | 4.12.2020 12:00:00 | 1.5 | +--------------------+---------+ table2 +--------------------+---------+ |

问题 This question already has answers here : Select values that meet different conditions on different rows? (6 answers) Closed 2 years ago . A MySQL database contains two tables with a one-to-many relationship: One user can have many settings: Users: id username password -------------------------- 1 Bob 123 2 Alice abc ... Settings: id user_id key value ----------------------------- 1 1 color blue // Bobs settings... 2 1 theme xy 3 1 size 5 4 2 size 5 // Alices settings... Problem: How to find

问题 I have a view A and a view B . In A I have a lot of information about some systems, like IP and port which I want to preserve all. In B I have just one information that I want to add at A . The matching fields between the two views are IP and Port . So I have to match those hosts which has the same IP and Port in both views. Examples: View A: IP | OS | Hostname | Port | Protocol 1 | Win | hostONE | 80 | tcp 1 | Win | hostONE | 443 | tcp 1 | Win | hostONE | 8080 | tcp 2 | Linux | hostTWO | 21

问题 I have a view A and a view B . In A I have a lot of information about some systems, like IP and port which I want to preserve all. In B I have just one information that I want to add at A . The matching fields between the two views are IP and Port . So I have to match those hosts which has the same IP and Port in both views. Examples: View A: IP | OS | Hostname | Port | Protocol 1 | Win | hostONE | 80 | tcp 1 | Win | hostONE | 443 | tcp 1 | Win | hostONE | 8080 | tcp 2 | Linux | hostTWO | 21