Wish SQLite: ExecuteQuery2 and Cursor.GetColumnName

LucaMs

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• Sep 7, 2015

• #1

If you use ExecuteQuery2, field names returned by Cursor1.GetColumnName will be all "?" (as in the query).

I would prefer to receive the real names of the fields, of course.


Thank you

 

Last edited: Sep 7, 2015

Erel

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• Sep 7, 2015

• #2

It shouldn't happen. Can you upload a small example?

 

LucaMs

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• Sep 7, 2015

• #3

Attached.

Thank you

 

Attachments

• ExecuteQuery2 Test.zip

  11.8 KB · Views: 294

LucaMs

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• Sep 7, 2015

• #4

I forgot to write:

B4X:

For i = 0 To Cur.RowCount - 1
    Cur.Position = i
    Log(Cur.GetString("Name"))
Next

Field "Name" will "not exist"; "?" and "?" will exist.

 

M

Mahares

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• Sep 7, 2015

• #5

@LucaMs
You cannot parametize field names in the SQL statement like you have here as far as I know:
Query = "SELECT ?, ? FROM tbl"

 

LucaMs

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• Sep 7, 2015

• #6

Mahares said:

@LucaMs
You cannot parametize field names in the SQL statement like you have here as far as I know:
Query = "SELECT ?, ? FROM tbl"

Click to expand...

Why not? Each "?" will be correctly replaced, it works.

Moreover, in some cases I may not know a priori the name of the fields to be selected.

I don't know if ExecuteQuery2 is a B4A or Java command. If it is B4A, Erel can modify it.

 

M

Mahares

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• Sep 7, 2015

• #7

LucaMs said:

Why not? Each "?" will be correctly replaced, it works.

Click to expand...

I do not get an error with this statement either, but it does not mean it is correct, even though the field name is 'name' and not LucaMS:
Cur = mDB.ExecQuery2(Query, Array As String("ID", "LucaMS"))
Also, I can do this: Query = "SELECT ?, ?, 'Erel', 'Klaus' FROM tbl" and not get an error.
See this link:
http://stackoverflow.com/questions/...terize-the-table-name-in-a-prepared-statement

 

Erel

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• Sep 7, 2015

• #8

Mahares is correct. You cannot replace field names and table names with question marks.
Parameterized queries is a feature of the SQL engine. It is not a simple string replacement.