准备好的声明是什么？

Question

我看到在.log文件中Postgres的pg_log目录中的一堆线是这样说：

ERROR: prepared statement "pdo_pgsql_stmt_09e097f4" does not exist

什么是预处理语句，并能造成什么样的事情来显示这些错误信息？

Answer 1

从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.

搜索网，我发现了“pdo_pgsql_stmt”命令是从某种PHP连接到数据库中。也许this link可以帮助你找到一个可以发送你的错误消息的套房邮件列表或问题跟踪器？

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编辑：我想我发现你的错误在这里：

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

Answer 2

我认为这将帮助你： http://jdbc.postgresql.org/documentation/81/server-prepare.html

基本上看起来像可以预编译存储过程。