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SQL Subqueries With Example

SQL Sub-queries

  • A sub-query is a SQL query within a query.
  • Sub-queries are nested queries that provide data to the enclosing query.
  • Sub-queries can return individual values or a list of records
  • Sub-queries m

The SQL sub-query syntax

There is no general syntax; sub-queries are regular queries placed inside parenthesis.
Sub-queries can be used in different ways and at different locations inside a query:
Here is an sub-query with the IN operator
  1. SELECT column-names FROM table-name1 WHERE value IN (SELECT column-name FROM table-name2 WHERE condition)

Sub-queries can also assign column values for each record:
  1. SELECT column1 = (SELECT column-name FROM table-name WHERE condition),column-names FROM table-name WHERE condition

SQL Sub-query Examples

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