Validation Frequency
Select a date and time using the calendar.
WHERE clause
Select a column with the Expression Helper or enter a clause up to 1,000 characters to restrict validation to part of the table. You can specify a partial table checksum based on a range or value in a column. The clause can include any columns of a table.
For example:
column_x,=current_data - X
column_y.= LAST_UPDATE_DATE
Table location | Column information |
---|---|
Teradata Database system and Aster system | Teradata Database system |
Teradata Database system and Hadoop system | Teradata Database system |
Teradata Database system, Aster system, and Hadoop system | Teradata Database system |
Aster system and Hadoop system | Aster system |
Validation Expression
Use the Expression Helper to create a valid expression, up to 500 characters for a custom table validation on a set of rows.
Expression Helper Function | Description |
---|---|
SUM | Aggregate expression that returns the arithmetic sum of the specified columns – usage: SUM(column name) |
AVERAGE |
Aggregate expression that returns the average value of the specified column – usage: AVG(column name) |
MIN | Aggregate expression that returns minimum value of the specified column - usage: MIN(columnName) |
MAX | Aggregate expression that returns the large value of the specified column - like MAX(column name) |
COUNT | Aggregate expression that returns a total of non-null occurrences of the specified column – usage: COUNT(columnName) |
CASE | Case expression always returns a numeric value. For example, CASE WHEN StateCode='CA' THEN 1 ELSE 0 END: |
HASHROW | Hash function returns the hexadecimal row hash value for an expression – usage: HASHROW(column1, column2) |
HASHBUCKET | Hash function returns the hash bucket number that corresponds to a specified row hash value – usage: HASHBUCKET(HASHROW(columnName1, columnName2)) |
Do not add tokens or SELECT, INSERT, MERGE, UPDATE, CREATE, DELETE, or DROP statements.
Hadoop RowCount Column
The field Hadoop rowcount column is applicable for table validation involving a Hadoop system. For a table validation on a Hadoop system, enter the name of only one column from all the columns in that table. It is recommended that you choose the column that is smallest in width.
Row Count
Select Row Count to measure whether tables have the same number of rows. It does not indicate if the content of the rows is different.