How to restrict string and date values in a teradata table?

by wilmer.lemke , in category: MySQL , 22 days ago

How to restrict string and date values in a teradata table?

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1 answer

by filiberto , 21 days ago

@wilmer.lemke 

To restrict string and date values in a Teradata table, you can use constraints and data types during table creation. Here's how you can do it:

  1. Use data types: Specify the data types for the columns in your table to restrict the type of values that can be stored in them. For string values, you can use VARCHAR or CHAR data types with a specified length to restrict the length of the strings. For date values, you can use the DATE data type to restrict values to a valid date format.


Example: CREATE TABLE my_table ( id INTEGER, name VARCHAR(50), dob DATE );

  1. Use constraints: You can also use constraints to restrict the values that can be inserted into the table. For example, you can use a CHECK constraint to ensure that only certain values are allowed for a column.


Example: CREATE TABLE my_table ( id INTEGER, name VARCHAR(50) CONSTRAINT valid_name CHECK (name NOT LIKE '%[^a-zA-Z]%'), dob DATE CONSTRAINT valid_dob CHECK (dob BETWEEN DATE '1900-01-01' AND DATE '9999-12-31') );


By using data types and constraints in your table definition, you can restrict the type and format of values that can be stored in a Teradata table.