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Query with variables doesn't work in the MySQL + dbExpress + Delphi stack

Practice




dbExpress driver does not support the TDBXTypes.UNKNOWN data type. Vendor error message:

when using variables, the query doesn't work in the mysql+dbexpress+delphi combination



SET @ostat_sum = 0;
@ostat_sum := @ostat_sum + prixod-rasxod AS ostat


I have the same problem
http://www.sql.ru/forum/actualthread.aspx?tid=879755


here's a similar problem, but it was never solved

here
http://www.sql.ru/forum/actualthread.aspx?tid=920790
looks like they sort of solved it, but the ostat column ends up in the result table as a blob, which really slows things down

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Lectures and tutorial on "Databases - MySql (Maria DB)"

Terms: Databases - MySql (Maria DB)

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