Deletes selected rows from a database table.
(This function is equivalent to a SQL DELETE statement.)
|
Function |
Group |
Execution |
Windows |
Embedded |
Thin Client |
| DBDelete
|
Database/ERP |
Synchronous |
Supported |
Supported |
Supported |
Note: This
feature emulates SQL (Structured Query Language) database
operations. You should be familiar with how SQL commands are formed
and executed before you use this feature.
Syntax
DBDelete( strDBConn, strTable, strCondition, "optStrErrorTag" )
- strDBConn
- The name of the database connection. Connections are
configured in the
Database/ERP folder.
- strTable
- The name of the table in the database.
- strCondition
- A string that specifies which rows of the table to
select. This is equivalent to the SQL WHERE clause, and the string
should follow the same syntax.
Tip: To delete
all rows in the table, make the condition statement a single space
(" ").
- optStrErrorTag
- The name of a String tag that will receive detailed
error messages, if errors occur during runtime.
Note: The tag
name must be enclosed in quotes, as shown in the syntax diagram, or
else the project will try to get the value of the named tag.
This is an optional parameter.
Returned value
Returns the number of rows deleted from the table. In
case of error, returns a negative number.
Examples
As used in a Math worksheet:
|
Tag Name |
Expression |
|
nRowsDeleted
|
DBDelete( "DB1", "Table1", "Column1 >
1000", "TagError" ) // Deletes all rows in Table1 where the
value of Column1 is greater than 1000. The returned value (i.e.,
the number of rows deleted) is written to TagError. |
|
Tag |
DBDelete( "DB1", "Table1", " " ) //
Deletes all rows of Table1. |