In Oracle, the COALESCE function is used to return the value of the first non-null expression from multiple expressions. Its purpose is to return the value of the first non-null expression when given a set of expressions.<\/p>\n
The syntax of the COALESCE function is as follows:
\nCOALESCE(expr1, expr2, …)<\/p>\n
Among them, expr1, expr2, and so on are the expressions to be checked, which can be multiple. The function evaluates these expressions in order and returns the value of the first non-empty expression. If all expressions are empty, it returns NULL.<\/p>\n
Here is an example:
\nSELECT COALESCE(NULL, \u2018Hello\u2019, NULL, \u2018World\u2019);<\/p>\n
In the example mentioned above, the COALESCE function evaluates each expression in order until it finds the first non-null expression. In this case, it returns ‘Hello’ as the result.<\/p>\n","protected":false},"excerpt":{"rendered":"
In Oracle, the COALESCE function is used to return the value of the first non-null expression from multiple expressions. Its purpose is to return the value of the first non-null expression when given a set of expressions. The syntax of the COALESCE function is as follows: COALESCE(expr1, expr2, …) Among them, expr1, expr2, and so […]<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_import_markdown_pro_load_document_selector":0,"_import_markdown_pro_submit_text_textarea":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-21185","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"yoast_head":"\n