Database instance error

Five instances were completed last week, and some errors occurred. Some errors were extremely low-level. The most important part of coding is carefulness! Example 1: strSQLSELECT password FROM system user WHERE UserName. Error cause: Double quotation marks instead of single quotation marks. 1st double quotation marks will actually match 2nd double quotation marks.

Five instances were completed last week, and some errors occurred. Some errors were extremely low-level. The most important part of coding is carefulness! Example 1: strSQL = SELECT password FROM system user WHERE UserName = 'username'. Error cause: Double quotation marks are not added, but double quotation marks. 1st double quotation marks are actually matched with 2nd double quotation marks.

Five instances were completed last week, and some errors occurred. Some errors were extremely low-level. The most important part of coding is carefulness!

Instance 1: StrSQL = "SELECT password FROM system user WHERE UserName = '" & UserName & "'", error cause:Double quotation marks instead of single quotation marks. The 1st double quotation marks are actually matched with the 2nd double quotation marks, so an error occurs, and no space is added before the password.

Example 2: you cannot find the desired MicrosoftAccess Driver (*. mdb) when you open the data source Manager in the Start Program ).

Open C: \ Windows \ syswow64and open an odbcad32.exe file to set the access data source. The specific cause is still being queried.

Example 3: there are no major errors. The key is to be careful.

Example 4:

This indicates that the project identity is not found in the database. You can add the project identity to the data source.

Example 5:

The reason is that the setting in the red box below is too small.

After several weeks of study, I have a certain understanding of the database and want to continue to study hard.