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Re: How to use aliases with SqlExp? [message #50328 is a reply to message #50327]

Fri, 21 September 2018 11:51

mirek
Messages: 13975
Registered: November 2005

Ultimate Member

Patisab wrote on Fri, 21 September 2018 11:08

Good morning Mirek,

When i declare the alias T2 for table T1 as an other ID (with SqlId or with SQLID macro i have compiling errors. This
SqlId T2("T1");
SQL & Select(ID.Of(TABLE),COL1.Of(TABLE),COL2.Of(TABLE),COL1.Of(T2),COL2.Of(T2))
.From(TABLE)
.InnerJoin(TABLE).AsTable(T2).On(ID.Of(T2) == FATHER.Of(TABLE));
results
error: 'class Upp::SqlSet' has no member named 'On'
and that
SqlId T2("T1");
SQL & Select(ID.Of(TABLE),COL1.Of(TABLE),COL2.Of(TABLE),COL1.Of(T2),COL2.Of(T2))
.From(TABLE)
.InnerJoin(T2).On(ID.Of(T2) == FATHER.Of(TABLE));
results
note:   crosses initialization of 'Upp::SqlId T2'
Sorry, i probably not understand your explanations

Best regards.

Ah, sorry I have missed improper use of AsTable. That has a little bit different meaning... (see https://www.ultimatepp.org/src$Sql$SqlExp_en-us.html)

Try this:

SqlId T2("T2");
SQL & Select(ID.Of(TABLE),COL1.Of(TABLE),COL2.Of(TABLE),COL1.Of(T2 ),COL2.Of(T2))
.From(TABLE)
.InnerJoin(TABLE.As(T2)).On(ID.Of(T2) == FATHER.Of(TABLE));

or this:

SqlId T2("T2");
SQL & Select(TABLE(ID ,COL1, COL2), T2(COL1, COL2))
.From(TABLE)
.InnerJoin(TABLE.As(T2).On(ID.Of(T2) == FATHER.Of(TABLE));

BTW, I think you will also need to alias T2.COL1, T2.COL2 to retrieve proper values after fetch...

SqlId T2("T2");
SQL & Select(TABLE(ID ,COL1, COL2), T2(COL1.As("T2_COL1"), COL2.As("T2_COL2")))
.From(TABLE)
.InnerJoin(TABLE.As(T2).On(ID.Of(T2) == FATHER.Of(TABLE));

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