DESCRIBE statement

11min

OverviewDescribe statement show columns within a table and tables within a database. 
The Describe statement is recommended to use before creating a new table to avoid duplicate tables.
SyntaxDescribe DatabaseBelow is the basic syntax for describing tables within a database:
Describe database
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DESCRIBE DATABASE;
DESCRIBE DATABASE;
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Describe TableBelow is the basic syntax for describing columns within a table:
Describe table
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DESCRIBE TABLE table_name;
DESCRIBE TABLE table_name;
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table_name is the name of the table that you want to show.
ExamplesTo get a better understanding of a DESCRIBE statement, take a look at some examples below:
Case #1: Describe Database1) In this example, we will figure out the columns of a part table. Run the query below:
Describe database
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DESCRIBE TABLE part;
DESCRIBE TABLE part;
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2) As a result, you will get a list of column names, column types, and nullable options from the part table.
Final output
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+----------------+------------+-------------+-------+----------+ 
| database_name  | table_name |    name     | type  | nullable |
+----------------+------------+-------------+-------+----------+
| public         | part       | p_partkey   | INT   | f        |
| public         | part       | p_name      | TEXT  | f        |
| public         | part       | p_mfgr      | TEXT  | f        |
| public         | part       | p_category  | TEXT  | f        |
| public         | part       | p_brand     | TEXT  | f        |
| public         | part       | p_color     | TEXT  | f        |
| public         | part       | p_type      | TEXT  | f        |
| public         | part       | p_size      | INT   | f        |
| public         | part       | p_container | TEXT  | f        |
+----------------+------------+-------------+-------+----------+

+----------------+------------+-------------+-------+----------+ 
| database_name  | table_name |    name     | type  | nullable |
+----------------+------------+-------------+-------+----------+
| public         | part       | p_partkey   | INT   | f        |
| public         | part       | p_name      | TEXT  | f        |
| public         | part       | p_mfgr      | TEXT  | f        |
| public         | part       | p_category  | TEXT  | f        |
| public         | part       | p_brand     | TEXT  | f        |
| public         | part       | p_color     | TEXT  | f        |
| public         | part       | p_type      | TEXT  | f        |
| public         | part       | p_size      | INT   | f        |
| public         | part       | p_container | TEXT  | f        |
+----------------+------------+-------------+-------+----------+
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The example above shows that the tables reside in the public schema, the default schema in Oxla. You can also have a table from other schemas - click here for more info.
Case #2: Describe Table1) Execute the following query to describe the database:
Describe table
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DESCRIBE DATABASE;
DESCRIBE DATABASE;
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2) You will retrieve a list of the existing tables in the database as shown below:
Final output
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+-----------------------------+
| name                        | 
+-----------------------------+
| supplier_scale_1_no_index   | 
| features                    | 
| orders                      | 
| features2                   | 
| featurestable               | 
| featurestable1              | 
| featurestable10             | 
+-----------------------------+
+-----------------------------+
| name                        | 
+-----------------------------+
| supplier_scale_1_no_index   | 
| features                    | 
| orders                      | 
| features2                   | 
| featurestable               | 
| featurestable1              | 
| featurestable10             | 
+-----------------------------+
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