This Oracle tutorial explains how to use the Oracle/PLSQLCASE statementwith syntax and examples. Description The Oracle/PLSQL CASE statement has the functionality of an IF-THEN-ELSE statement. Starting in Oracle
SQL>show userUSER为"HR"SQL>SELECTfirst_name,last_name,department_id,2CASEdepartment_id3WHEN10THEN'Accounting'4WHEN20THEN'Sales'5WHEN30THEN'Finance'6ELSE'Other'7ENDdepartment_name8FROMemployees where rownum<2;FIRST_NAMELAST_NAMEDEPARTMENT_IDDEPARTMENT_NAME---Steven King90OtherSQL> ※测试使用的Orac...
Functionally these are similar to a series if-elsif statements in PL/SQL. So you may be wondering why bother withcasestatements? Case statements can raise acase_not_foundexception. This happens if they run without processing one of the clauses. i.e. none of thewhenconditions are true and t...
oracle.javatools.db.sql Contains an API for declaratively parsing SQL queries (SELECT statements). Uses ofCaseStatement.WhenTheninoracle.javatools.db.sql Methods inoracle.javatools.db.sqlthat returnCaseStatement.WhenThen Modifier and TypeMethod and Description ...
and checking multiple conditions, all in a SQL query itself. Moreover, using the CASE function, multiple conditions provided in separate SQL queries can be combined into one, thus avoiding multiple statements on the same table (example given below). The function is available from Oracle 8i ...
Oracle SQL中的Case语句是一种条件表达式,用于根据不同的条件执行不同的操作。它可以在SELECT、UPDATE和DELETE语句中使用。 Case语句有两种形式:简单Case表达式和搜索Case表达式。 简单Case表达式:简单Case表达式用于将一个表达式与一系列可能的值进行比较,并在匹配时执行相应的操作。它的语法如下: 代码语言:txt 复制 CA...
CASE selector WHEN selector_value_1 THEN statements_1 WHEN selector_value_1 THEN statement_2 ... ELSE else_statements END CASE; Code language: PostgreSQL SQL dialect and PL/pgSQL (pgsql) Let’s examine the syntax of the simple CASE statement in detail: 1) selector The selector is an...
注意:集合操作的所有查询返回的列数、列类型必须相同,但是列名可以不一样。 2、translate 函数 translate(x, str1, str2) . 在字段x 中查找str1中的字符,转化为str2中对应的字符。 例子: select translate(x, 'abc', 'xyz') from table1 对字段x中字符进行替换:a->x, b->y, x->z ...
statementsは、selectorと同じ値を持つselector_valueが存在せず、trueのdangling_predicateがない場合にのみ実行されます。 ELSE句を指定しないと、selectorと同じ値を持つselector_valueが存在せず、trueのdangling_predicateがない場合に、事前定義済例外CASE_NOT_FOUNDが発生します。
oracle sql小结(主要讲横列转换的例子)decode 以及case,--建表createtablekecheng(idNUMBER,nameVARCHAR2(20),courseVARCHAR2(20),scoreNUMBER);--插入数据insertintokecheng(id,name,course,score)values