SQL语句 EXPLAIN 更新时间:2025-05-02 23:00:01 描述 该语句用于解释 SQL 语句的执行计划,可以是SELECT、DELETE、INSERT、REPLACE或UPDATE语句。 EXPLAIN与DESCRIBE、DESC互为同义词。 语法 {EXPLAIN|DESCRIBE|DESC}[explain_type]dml_statement;explain_type:BASIC|OUTLINE|EXTENDED|EXTENDED_NOADDR|PARTITIONS|FORMAT={...
Structure of the EXPLAIN Result TableSCHEMANAME CHAR (64) TABLENAME CHAR(64) COLUMN_OR_INDEX CHAR(64) STRATEGY CHAR(40) PAGECOUNT CHAR(10) The sequence in which the SELECT is processed is described by the order of the rows in the result table. ...
Figure 4: Execution plan accessing the SQL cursor cache, using the basic format The arguments accepted by DBMS_XPLAN.DISPLAY_CURSOR are: SQL ID (default null, means the last SQL statement executed in this session), child number (default 0), format, controls the amount of ...
With VERBOSE, the command provides additional details about the structure and flow of the execution plan, such as column and table specifics. This level of detail is helpful when debugging complex queries or working with views. Understanding the EXPLAIN Output: The EXPLAIN output includes several k...
Example 1: Analyzing a Basic Query Assume you have a table employees with columns id, name, and department. You want to analyze a query that selects employees from a specific department. Code: -- Analyze the query performance for filtering by department ...
you can quickly create a SQL Server 2022 instance on Windows Server 2019 with a couple of clicks, along with some basic information, such as the virtual machine name and SQL Server configuration details. Once provided, Azure Resource Manager initiates the creation of the virtu...
EXPLAIN PLAN SET statement_id = 'ex_plan2' FOR SELECT last_name FROM employees WHERE last_name LIKE 'Pe%'; SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY(NULL, 'ex_plan2','BASIC')); --- | Id | Operation | Name | --- | 0 | SELECT STATEMENT | | | 1 | INDEX RANGE ...
C# Int does not exist in current context when doing a basic math equasion C# interop - passing array of struct to a DLL. C# Interop.Excel || The remote procedure call failed. (Exception from HRESULT: 0x800706BE) C# Linq Group By on multiple columns C# LINQ List<KeyValuePair<string,...
Since the introduction of redstone objects (materials used to create basic electric circuits within the game) people have made many machines within Minecraft, including calculators and clocks. The most complex of these machines simulate simple computers, capable of storing several lines of code and ...
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