Search results
8 lis 2018 · select A.* from table_A A where A.id in ( select B.id from table_B B where B.tag = 'chair' ) Alternatively you could join the tables and filter the rows you want: select A.* from table_A A inner join table_B B on A.id = B.id where B.tag = 'chair'
2 paź 2013 · Use the EXISTS clause evaluating whether a row in the outer query should be included or excluded without changing the query output. This is second part of 2-part series on SQL clauses. Juan covered the IN() in the first part.
14 cze 2022 · Use the EXISTS predicate (with the optional NOT reserved word) in true/false comparisons to determine whether the subquery returns any records. You can also use table name aliases in a subquery to refer to tables listed in a FROM clause outside the subquery.
To combine data from two data sources based on values in fields that have different data types, you create a WHERE clause that uses one field as a criterion for the other field, by using the LIKE keyword.
21 sty 2022 · Use the WHERE clause to eliminate records you don't want grouped by a GROUP BY clause. Use various expressions to determine which records the SQL statement returns. For example, the following SQL statement selects all employees whose salaries are more than $21,000: SELECT LastName, Salary FROM Employees WHERE Salary > 21000;
22 mar 2022 · To perform this operation, the Microsoft Jet database engine searches the specified table or tables, extracts the chosen columns, selects rows that meet the criterion, and sorts or groups the resulting rows into the order specified. SELECT statements do not change data in the database. SELECT is usually the first word in an SQL statement.
In order to filter the student records that have a 10 grade in Math, we can use the EXISTS SQL operator, like this: SELECT id, first_name, last_name FROM student WHERE EXISTS ( SELECT 1 FROM student_grade WHERE student_grade.student_id = student.id AND student_grade.grade = 10 AND student_grade.class_name = 'Math' ) ORDER BY id
