VbzCart/queries

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VbzCart: data views

Overview

"Views" in MySQL are like SELECT "queries" in MS Access, i.e. they pull data from existing tables and are themselves usable as data sources in much the same way that tables are (and in which result sets from functions are not).

Views

Some common prefixes:

• qryCbx_: queries used for filling comboboxes. The unique ID will always be the first field, and the text to display will always be the second field; additional fields may be provided for use in further qryCbx_ queries which show a subset of the results.
• qryCat_: queries which build catalog numbers or information by joining multiple tables. (In Access, the convention was qryCatNum_.)

qryCat_Depts

<mysql> CREATE OR REPLACE VIEW qryCat_Depts AS

 SELECT
   d.ID,
   d.Name,
   d.Sort,
   d.CatKey,
   d.ID_Supplier,
   CONCAT_WS('-',s.CatKey,d.CatKey) AS CatNum
 FROM depts AS d LEFT JOIN suppliers AS s ON d.ID_Supplier=s.ID;</mysql>

qryCat_Titles

<sql>CREATE OR REPLACE VIEW qryCat_Titles AS

 SELECT
   t.ID,
   t.Name,
   CONCAT_WS('-',d.CatNum,t.CatKey) AS CatNum,
   d.ID_Supplier,
   t.ID_Dept,
   t.DateAdded,
   t.RstkMin AS QtyMin_Rstk,
   t.Notes,
   t.Supplier_CatNum AS Supp_CatNum
 FROM titles AS t LEFT JOIN qryCat_Depts AS d ON t.ID_Dept=d.ID;</sql>

qryCat_Items

<sql>SELECT

 i.ID,
 i.ID_Title,
 (t.ID IS NOT NULL) AS TitleExists,
 t.ID_Supplier,
 i.PriceSell,
 i.PriceList,
 i.PriceBuy,
 i.CatNum,
 t.CatNum AS Title_CatNum,
 t.Name AS Title_Name,
 i.ID_ItTyp,
 i.ID_ItOpt,
 i.ItOpt_Descr,
 i.ItOpt_Sort,
 CONCAT(t.Name, IF
     (i.ItOpt_Descr IS NULL,,CONCAT(
       ' (',i.ItOpt_Descr,')'
       )
     )
   ) AS Descr,
 i.Supp_CatNum,
 i.isForSale,
 i.isPulled,
 i.QtyMin_Stk,
 t.QtyMin_Rstk AS QtyMin_Rstk_Title

FROM cat_items AS i LEFT JOIN qryCat_Titles AS t on i.ID_Title=t.ID ORDER BY t.ID IS NOT NULL, i.CatNum, i.ItOpt_Sort;</sql>

• MySQL note: Functions (or CONCAT, anyway) apparently do not like being separated from their opening parenthesis; it seems to resolve the function name as a field name, and (generally) will report that there is no such field.

qryCbx_Items

<sql>SELECT

 i.ID,
 CONCAT(
   IF(i.isPulled,CONCAT('!PULLED (',i.ID,')'),),
   i.CatNum,
   IF(i.Supp_CatNum IS NULL,,CONCAT('[',i.SuppCatNum,']')),
   IF(i.isForSale,,' n/a'),
   i.Descr)
     AS Descr,
 i.isForSale

FROM qryCat_Items AS i ORDER BY NOT i.isPulled, i.isForSale, i.CatNum;</sql>