1、id的含义 The SELECT identifier. This is the sequential number of the SELECT within the query. The value can be NULL if the row refers to the union result of other rows. In this case, the table column shows a value like <unionM,N> to indicate that the row refers to the union of...
MySQL explains how it would process the statement, including information about how tables are joined and in which order. For information about using EXPLAIN to obtain execution plan information, see Section 8.8.2, “EXPLAIN Output Format”. 当...
{explainable_stmt|FORCONNECTION connection_id} {EXPLAIN|DESCRIBE|DESC} ANALYZE select_statement explain_type: { FORMAT=format_name } format_name: { TRADITIONAL|JSON|TREE } explainable_stmt: {SELECTstatement|TABLEstatement|DELETEstatement|INSERTstatement|REPLACE statement|UPDATEstatement } 示例: EXPLAIN fo...
Explain the following statement: There is no such thing as a free lunch in relation to scarce resources. Trade-Off: One of the fundamentals problems in economics is the problem of scarce resources. As resources are limited, our unlimited wants cannot be ...
Answer to: Consider the set: A=(a,b,c,d,e,f, cdots ,x,y,z), B=(v,d,t), C=(d,q,v,f), D=(d,t). Explain if the statement is True or False: D subset B...
statement, $2.explain_into_variable_name.length ? std::optional<std::string_view>( to_string_view($2.explain_into_variable_name)) : std::optional<std::string_view>(std::nullopt), $3.schema_name_for_explain); } ; describe_command 语义组用于解析 DESCRIBE、EXPLAIN 和DESC 关键字,详见...
The EXPLAIN statement provides information about how MySQL executes statements. EXPLAIN works with SELECT, DELETE, INSERT, REPLACE, and UPDATE statements. 通过一个实例来说明explain的用法,其实使用很简单,主要是通过实例来介绍explain各个输出项的使用。(实例中使用的数据是MySQL官方提供的测试数据) ...
I can't explain such a statement by him on the basis of logic. He must have blown his top. 我从逻辑推理方面解释不了他讲的这番话,他想必是神经错乱了. 《现代汉英综合大词典》 He will explain it fully once and for all. 他将把它充分地解释一次就此了结. 《简明英汉词典》 Many theories pur...
4 If his statement does not throw light on the subject, heA can explain the subject clearlyB can hardly make himself understood concenin on the subject5 If the emperor was very cruel to his people, he___A treated his people kindlyB...
| UPDATE statement } 示例: EXPLAIN format = TRADITIONAL json SELECT tt.TicketNumber, tt.TimeIn, tt.ProjectReference, tt.EstimatedShipDate, tt.ActualShipDate, tt.ClientID, tt.ServiceCodes, tt.RepetitiveID, tt.CurrentProcess, tt.CurrentDPPerson, ...