WHERE name IN ('Google','菜鸟教程'); 1. 2. IN 与 = 的异同 相同点:均在WHERE中使用作为筛选条件之一、均是等于的含义 不同点:IN可以规定多个值,等于规定一个值 IN SELECT column_name(s) FROM table_name WHERE column_name IN (value1,value2,...); = SELECT column_name(s) FROM table_name...
Here is my code SELECTID, Name, PhoneFROMTable1LEFTJOINTable2ONTable1.ID=Table2.IDWHERETable1.ID=12ANDTable2.IsDefault=1 The problem happens when Table2 is null, so, the query returns nothing. How do I leave the last part of the queryAND Table2.IsDefault = 1optional? I've tried ...
WHERE Clause with AND, OR Operators We can use AND and OR operators together in SQL to combine multiple conditions in a WHERE clause to filter rows that meets the specified criteria. The AND operator will make sure only those rows are filtered that satisfy all the conditions and the OR oper...
shippedDate AND o2.orderNumber = 10293; 这当然也可以通过子查询来实现: SELECT orderNumber, shippedDate, customerNumber FROM orders WHERE shippedDate = (SELECT shippedDate FROM orders WHERE orderNumber = 10293); 虽然得到的结果是完全相同的,但有时候自连接的效率会明显比子查询更高。 我们也可以使用自...
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使用关联查询,并用组合的字段,起别名的方式过滤,报错提示:SQL 错误 [1052] [23000]: Column 'code' in where clause is ambiguous selectconcat(ti.code,'-', sti.code)ascode, sti.*, ti.nameastask_namefromsub_task_info stileftjointask_info tionti.id=ti.task_idwherecodelike'%001%'; ...
This SQL tutorial explains how to use the SQL WHERE clause with syntax and examples. The SQL WHERE clause is used to filter the results and apply conditions in a SELECT, INSERT, UPDATE, or DELETE statement.
关键词(keyword)子句(clause) -WHERE(指定) -AND(与) -BETWEEN 在指定的两个值之间 - IS NULL 为NULL值 - 子句为非数字需 ‘’ 子句操作符 -[= 等于 , > 大于 ,< > 不等于 , >= 大于等于 , != 不等于, !> 不大于 ,< 小于 , <= 小于等于 ,!< 不小于.] 技术速查 --检索prod_price列中...
A WHERE clause allows adding several conditions as follows: Retrieving Rows that Meet Several WHERE Conditions.This can be done using the AND operator. For example, if we need to retrieve all employees ("EM") named "Jean", we should use the following SQL command: ...
WhereClause WhileStatement WindowClause WindowDefinition WindowDelimiter WindowDelimiterType WindowFrameClause WindowFrameType WindowsCreateLoginSource WithCtesAndXmlNamespaces WithinGroupClause WitnessDatabaseOption WlmTimeLiteral WorkloadClassifierOption WorkloadClassifierOptionType WorkloadClassifierStatement Workload...