準備好的聲明是什麼？

Question

我看到在.log文件中Postgres的pg_log目錄中的一堆線是這樣說：

ERROR: prepared statement "pdo_pgsql_stmt_09e097f4" does not exist

什麼是預處理語句，並能造成什麼樣的事情來顯示這些錯誤信息？

Answer 1

從the documentation：

A prepared statement is a server-side object that can be used to optimize performance. When the PREPARE statement is executed, the specifie statement is parsed, rewritten, and planned. When an EXECUTE command is subsequently issued, the prepared statement need only be executed. Thus, the parsing, rewriting, and planning stages are only performed once, instead of every time the statement is executed.

搜索網，我發現了「pdo_pgsql_stmt」命令是從某種PHP連接到數據庫中。也許this link可以幫助你找到一個可以發送你的錯誤消息的套房郵件列表或問題跟蹤器？

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編輯：我想我發現你的錯誤在這裏：

http://bugs.php.net/bug.php?id=37870

Answer 2

我認爲這將幫助你： http://jdbc.postgresql.org/documentation/81/server-prepare.html

基本上看起來像可以預編譯存儲過程。