Re: [HACKERS] preprocessor question: prepare statement
От | Thomas G. Lockhart |
---|---|
Тема | Re: [HACKERS] preprocessor question: prepare statement |
Дата | |
Msg-id | 36B90A38.339D6B16@alumni.caltech.edu обсуждение исходный текст |
Ответ на | preprocessor question: prepare statement (Michael Meskes <Michael.Meskes@usa.net>) |
Ответы |
Re: [HACKERS] preprocessor question: prepare statement
Re: [HACKERS] preprocessor question: prepare statement |
Список | pgsql-hackers |
> Could anyone tell me whether the EXEC SQL PREPARE statement is to be > interpreted by the preprocessor or during run-time? That is can it be > placed outside a function? Does it have to stand above the DECLARE or > EXECUTE statement that references it or does it have to be executed > prior to this statement? > The DECLARE statement AFAIK is to be processed by the preprocessor. > Hopefully that one is correct too. :-) Pretty sure that PREPARE is a run-time thing, since you can dynamically build the sql statement fed to PREPARE. In fact, looking at my Ingres docs: "Dynamic SQL has four statements that are exclusively used in a dynamic program: 'execute immediate', 'prepare', 'execute', and 'describe'." In another section, it says: "The 'prepare' statement tells the DBMS to encode the dynamically built statement and assign it the specified name. After a statement is prepared, the program can execute the statement one or more times within a transaction by issuing the 'execute' statement and specifying the statement name. This method improves performance if your program must execute the same statement many times in a transaction. When you commit a transaction, all statements that were prepared during the transaction are discarded." Hope this helps... - Tom
В списке pgsql-hackers по дате отправления: