| --- |
| { |
| "title": "CONCAT", |
| "language": "en" |
| } |
| --- |
| |
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| |
| ## concat |
| ### Description |
| #### Syntax |
| |
| `VARCHAR concat (VARCHAR,...)` |
| |
| |
| Connect multiple strings and return NULL if any of the parameters is NULL |
| |
| ### example |
| |
| ``` |
| mysql> select concat("a", "b"); |
| +------------------+ |
| | concat('a', 'b') | |
| +------------------+ |
| | ab | |
| +------------------+ |
| |
| mysql> select concat("a", "b", "c"); |
| +-----------------------+ |
| | concat('a', 'b', 'c') | |
| +-----------------------+ |
| | abc | |
| +-----------------------+ |
| |
| mysql> select concat("a", null, "c"); |
| +------------------------+ |
| | concat('a', NULL, 'c') | |
| +------------------------+ |
| | NULL | |
| +------------------------+ |
| ``` |
| ### keywords |
| CONCAT |