Delete
Do Record
Setting
Add New Item
Menu List
| Title | Content Type | Order | Action | ||||||
|---|---|---|---|---|---|---|---|---|---|
| {{kb_content.name}} {{kb_content.name}} | {{setValue(content_types, kb_content.content_type)}} | {{kb_content.sort_order}} | Preview Edit Edit Content | ||||||
| {{kb_content.name}} | {{setValue(content_types, kb_content.content_type)}} | {{kb_content.sort_order}} | Preview Edit Edit Content | ||||||
| No record | |||||||||
Status: published
Programming, Software and application
2020-12-07 03:13:23
Oracle Union
1809
Introduction to Oracle Database Oracle Tables and Data definition Modifying data Oracle Query and Filter Oracle data types Joining tables Oracle Operators Grouping data Constraints
এই কোর্সে যা থাকছে
৩টি বিষয়
৮০টি লাইভ ক্লাস
The Oracle UNION operator is used to combine the result sets of 2 or more Oracle SELECT statements. It removes duplicate rows between the various SELECT statements.
Each SELECT statement within the UNION operator must have the same number of fields in the result sets with similar data types.
Syntax
The syntax for the UNION operator in Oracle/PLSQL is:
SELECT expression1, expression2, ... expression_n FROM tables [WHERE conditions] UNION SELECT expression1, expression2, ... expression_n FROM tables [WHERE conditions];
Parameters or Arguments
expression1, expression2, expression_n
The columns or calculations that you wish to retrieve.
tables:
The tables that you wish to retrieve records from. There must be at least one table listed in the FROM clause.
WHERE conditions
Optional. The conditions that must be met for the records to be selected.
Note
There must be same number of expressions in both SELECT statements.