Oracle教程 2023-04-02

Oracle 视图 V$SQL_BIND_METADATA 官方解释，作用，如何使用详细说明

V$SQL_BIND_METADATA 是 Oracle 中的动态视图，它查询可重用语句的绑定信息。它包括变量名、变量类型、变量值的描述性属性以及与此语句关联的表和列的信息。SQL 引擎使用这些属性来收集优化信息。

使用V$SQL_BIND_METADATA视图获取SQL语句的绑定信息，要做到这一点，请确保SQL_ID字段已被正确填充，以便根据SQL_TEXT字段重新构造引用语句并将绑定变量值传递给语句的实例。可以使用以下SQL查询V$SQL_BIND_METADATA：

SELECT *
FROM V$SQL_BIND_METADATA
WHERE SQL_ID = :sql_id;

V$SQL_BIND_METADATA describes metadata related to bind variables.

V$SQL_BIND_METADATA describes, for each distinct bind variable in each cursor owned by the session querying this view:

Bind metadata provided by the client, if the bind variable is user defined
Metadata based on the underlying literal, if the CURSOR_SHARING parameter is set to FORCE and the bind variable is system-generated.

Column	Datatype	Description
`ADDRESS`	`RAW(4 \| 8)`	Memory address of the child cursor that owns this bind variable
`POSITION`	`NUMBER`	Bind position
`DATATYPE`	`NUMBER`	Internal identifier for the bind data type. Beginning in Oracle Database 12c, a number representing a PL/SQL data type can appear in this column.
`MAX_LENGTH`	`NUMBER`	Maximum length of the bind value
`ARRAY_LEN`	`NUMBER`	Maximum number of array elements (for array binds only)
`BIND_NAME`	`VARCHAR2(128)`	User-defined or system-generated bind variable name (if used)
`CON_ID`	`NUMBER`	The ID of the container to which the data pertains. Possible values include: `0`: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs. `1`: This value is used for rows containing data that pertain to only the root n: Where n is the applicable container ID for the rows containing data