数据集
if 参数=1
select * from tb1
if 参数=2
select * from tb2
if 参数=3
select * from tb3
这种应该怎么写,求指点
${if(参数=1,"select * from tb1","select * from tb2")}
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${switch(参数,1,"select * from tb1",2,"select * from tb2",3,"select * from tb3")}
${if(参数='1',"SELECT * FROM 表1",switch(参数,'2',"SELECT * FROM 表2",'3',"SELECT * FROM 表3"))}