


Determining the Length of a VARCHAR[n] Field with SQL
Question:
In a SQL table with a VARCHAR[n] field, how can you obtain its size, such as whether it's set to 1000 characters, using a single SQL statement?
Solution:
To retrieve the size of a VARCHAR[n] field, you can utilize the following steps:
select column_name, data_type, character_maximum_length from information_schema.columns where table_name = 'myTable'
In this query:
- column_name: Specifies the VARCHAR[n] field of interest.
- data_type: Indicates the data type of the field, which will be 'varchar'.
- character_maximum_length: Returns the maximum length of the VARCHAR field.
By executing this query, you will obtain the column's name, data type, and maximum character length, which will provide the desired size information for the VARCHAR[n] field.
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