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The UNION operator is a set operator that combines result sets of two or more SELECT statements into a single result set. The following illustrates the syntax of the UNION operator that combines the result sets of two queries: SELECT column_list_1 FROM T1 UNION SELECT column_list_1 FROM T2; Code language: SQL (Structured Query Language) (sql)
UNION combines the result from multiple SELECT statements into a single result set. Example: mysql> SELECT 1, 2; . +---+---+. | 1 | 2 |. +---+---+. | 1 | 2 |. +---+---+. mysql> SELECT 'a', 'b'; . +---+---+. | a | b |. +---+---+. | a | b |. +---+---+. mysql> SELECT 1, 2 UNION SELECT 'a', 'b'; . +---+---+. | 1 | 2 |. +---+---+. | 1 | 2 |.
17 Μαΐ 2023 · MySQL UNION operator: definition and purpose. The syntax of MySQL UNION operator; Rules and restrictions of MySQL UNION; MySQL UNION vs. JOIN; MySQL UNION vs. UNION ALL; Practical examples and use cases. Example 1: Basic UNION; Example 2: UNION ALL; Example 3: UNION with a condition; Example 4: UNION with DISTINCT; Example 5: Simple UNION for ...
8 Σεπ 2008 · UNION. SELECT 'foo' AS bar. Result: +-----+. | bar |. +-----+. | foo |. +-----+. 1 row in set (0.00 sec) UNION ALL example:
25 Σεπ 2018 · The Union operator combines the results of two or more queries into a single result set that includes all the rows that belong to all queries in the Union. In simple terms, it combines the two or more row sets and keeps duplicates. For example, the table ‘A’ has 1,2, and 3 and the table ‘B’ has 3,4,5.
UNION combines the result from multiple query blocks into a single result set. This example uses SELECT statements: mysql> SELECT 1, 2; +---+---+ | 1 | 2 | +---+---+ | 1 | 2 | +---+---+ mysql> SELECT 'a', 'b'; +---+---+ | a | b | +---+---+ | a | b | +---+---+ mysql> SELECT 1, 2 UNION SELECT 'a', 'b'; +---+---+ | 1 | 2 | +---+---+ | 1 | 2 | | a ...
