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_Columns Table

The _Columns table is a read-only system table that contains the column catalog. It lists the columns for all the tables. You can query this table to find out if a given column exists.

The _Columns table has the following columns.

ColumnTypeKeyNullable
Table Text YN
Number Integer YN
Name Text NN

 

Columns

Table

The name of the table that contains the column.

Number

The order of the column within the table.

Name

The name of the column.

Remarks

Because the _Columns table is a system table that cannot be modified through SQL queries, you cannot obtain the primary keys with the MsiDatabaseGetPrimaryKeys function or the PrimaryKeys property.

Only persistent columns are stored in the _Columns table. To determine if a temporary column exists one would need to create a view using a SELECT * statement against the table, then loop through all fields in a record returned by the MsiViewGetColumnInfo function with the MSICOLINFO_NAMES option.

 

 

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