Field not found : "".
lazarus / 16-Databases

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Miflon · 2019-11-30 08:23

Hi everybody. Sorry for my poor english.
W10, Lazarus 2.0.6, PostgreSQL 12.0
I connect a form to PostgreSQL by the mean of SQLDB components
PQConnection and SQLTransaction. All went OK.
I drop three SQLQuery, three DataSource, three DBLookupComboBox, three
DBGrid (to check links between theses components) on the form. At
design time, the grids are populated correctly.
When the code is executed, the two firsts DBLookupComboBox works well
when selecting items but the third one throws an error :  SQLQuery3 :
Field not found : "".
I change the order of the components at design time, it's always the
third one that is showing error, regardless the query. When I put a
forth SQLQuery, DataSource and DBLookupComboBox, this one works fine.
I change my mind and use components from ZeosLib and all went OK.
The problem is worked around but not solved. It's not fulfilling for
me.
Someone can help me understanding or may be solving this problem.
Thanks in advance.
Michel.

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Thaddy · 2019-11-30 09:08

case sensitive? Pascal does not mind, but SQL does...
(We need some code, actually, but first check the case.)

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zeljko · 2019-11-30 10:19

Postgresql field/table names are case insensitive

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MarkMLl · 2019-11-30 10:29

[Checks] unless quoted using ""

MarkMLl

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Miflon · 2019-11-30 17:37

Thanks for your replies.
These are my tables and fields names :
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i
t_r_forme_for (for_id, for_rang, for_base, for_code,
for_libelle)t_r_materiau_mat (mat_id, mat_rang, mat_base, mat_code,
mat_libelle)t_r_pression_pre (pre_id, pre_rang, pre_base, pre_code,
pre_libelle)t_r_stucture_str (str_id, str_rang, str_base, str_code,
str_libelle)And the queries filling the DBLookupComboBox, no code,
just in Objects Inspector :
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i SELECT
for_id, for_libelle FROM s_ref.]t_r_forme_for;SELECT mat_id,
mat_libelle FROM s_ref.]t_r_materiau_mat;SELECT pre_id, pre_libelle
FROM t_r_pression_preSELECT str_id, str_libelle FROM
t_r_stucture_strNo need for ORDER BY for the DBLookupComboBox unlike
for the ComboBox to fetch the primary keys. Grids are filled properly
from these queries.
How explain the different behavior between lazarus components and Zeos
ones?
If you need some more details, don't hesitate!
Michel.