So I have a table where I have column A, B, C,D. Column A has values which have corresponding multiple values in column B.I need to check if all the values in column C and D are null for the…
The situation is quite similar to that shown in this question Select row from one table where multiple rows in another table have determined values, but the condition is more complex. I have two tables in MySQL: Products: id |…
sorry for the confusing title but I hope this explains my question. I have a tab delimited text file that looks like this if I were to display it as a table: ════════╤════════╤════════╤═════════╤═════════╤═════════╤═════════ item │ id │ info │ PERSON1…
I am trying to find a way to improve performance of 'Load data infile' command for InnoDB table, which is extremely slow. Generally I have been using MyISAM for more than 10 years, because this engine by design is the…
I have a table with a column for JSON. Example of the JSON in the column: “[{ “plys”: 3, “end”: 47.56, “length”: 47.56 }, { “plys”: 2, “end”: 62.97, “length”: 15.41 }]” There are other fields in each object that…
I'm new to SQL, I'm learning from a free youtube MySQL course for beginners. 2 days ago I gave myself a problem and now I found a work-around, but perhaps there are better ways to solve it. emp_id super_id 100…
I expected an error to occur with the following query, but instead, the query is executed in an unintended direction. Copy code SELECT MAX(A) FROM table_a; >> 1 SELECT A FROM (SELECT MAX(A) FROM table_a) AS TMP; >> ERROR SELECT…
all members see the same counts in the software. How can I make it count specifically for user_id? @php $check_count = AppModelsSupport::where('status', 2)->get() @endphp <li class="header__menu-item"> <span>Support</span> @if(count($check_count) == 0) @else <span class="notification notranslate">{{count($check_count)}}</span> @endif </li> mysql picture I wanted…
I have a table (say table t) with an index on col_a that is unique. Now the index on col_a is used in these 2 following cases - SELECT * from t WHERE(col_a,col_b) IN((x,y),(p,q)); - query_1 SELECT * from t…
When importing a CSV file into a MySQL database through phpMyAdmin, is there a way to get a warning if a value is not listed in the "values" list of a ENUM or SET field in the table's structure? Right…