A SELECT statement can consist of the following basic clauses.

• SELECT
• INTO
• FROM
• JOIN
• WHERE
• GROUP BY
• HAVING
• UNION
• ORDER BY
• LIMIT

SELECT Syntax

The following syntax diagram outlines the syntax supported by the Amazon Athena adapter:

SELECT {
  [ TOP <numeric_literal> | DISTINCT ]
  { 
    * 
    | { 
        <expression> [ [ AS ] <column_reference> ] 
        | { <table_name> | <correlation_name> } .* 
      } [ , ... ] 
  }
  { 
    FROM <table_reference> [ [ AS ] <identifier> ] 
  } [ , ... ]
  [ [ 
      INNER | { { LEFT | RIGHT | FULL  } [ OUTER ] }  
    ] JOIN <table_reference> [ ON <search_condition> ] [ [ AS ] <identifier> ] 
  ] [ ... ] 
  [ WHERE <search_condition> ]
  [ GROUP BY <column_reference> [ , ... ]
  [ HAVING <search_condition> ]
  [ UNION  [ ALL ] <select_statement> ]
  [ 
    ORDER BY 
    <column_reference> [ ASC | DESC ] [ NULLS FIRST | NULLS LAST ]
  ]
  [
    LIMIT <expression>
    [ 
      { OFFSET | , }
      <expression> 
    ]
  ] 
}

  <expression> ::=
    | <column_reference>
    | @ <parameter> 
    | ?
    | COUNT( * | { [ DISTINCT ] <expression> } )
    | { AVG | MAX | MIN | SUM | COUNT } ( <expression> ) 
    | NULLIF ( <expression> , <expression> ) 
    | COALESCE ( <expression> , ... ) 
    | CASE <expression>
        WHEN { <expression> | <search_condition> } THEN { <expression> | NULL } [ ... ]
    [ ELSE { <expression> | NULL } ]
      END 
    | <literal>
    | <sql_function> 

  <search_condition> ::= 
    {
      <expression> { = | > | < | >= | <= | <> | != | LIKE | NOT LIKE | IN | NOT IN | IS NULL | IS NOT NULL | ANY | ALL | EXISTS | NOT EXISTS | CONTAINS | NOT CONTAINS | BETWEEN | AND | OR } [ <expression> ]
    } [ { AND | OR } ... ]

Examples

1. Return all columns:
   

   SELECT * FROM [AwsDataCatalog].[sampledb].Customers

2. Rename a column:
   

   SELECT "TotalDue" AS MY_TotalDue FROM [AwsDataCatalog].[sampledb].Customers

3. Cast a column's data as a different data type:
   

   SELECT CAST(AnnualRevenue AS VARCHAR) AS Str_AnnualRevenue FROM [AwsDataCatalog].[sampledb].Customers

4. Search data:
   

   SELECT * FROM [AwsDataCatalog].[sampledb].Customers WHERE CustomerId = '12345'

5. The Amazon Athena APIs support the following operators in the WHERE clause: =, >, <, >=, <=, <>, !=, LIKE, NOT LIKE, IN, NOT IN, IS NULL, IS NOT NULL, ANY, ALL, EXISTS, NOT EXISTS, CONTAINS, NOT CONTAINS, BETWEEN, AND, OR.
   

   SELECT * FROM [AwsDataCatalog].[sampledb].Customers WHERE CustomerId = '12345';

6. Return the number of items matching the query criteria:
   

   SELECT COUNT(*) AS MyCount FROM [AwsDataCatalog].[sampledb].Customers 

7. Return the number of unique items matching the query criteria:
   

   SELECT COUNT(DISTINCT TotalDue) FROM [AwsDataCatalog].[sampledb].Customers 

8. Return the unique items matching the query criteria:
   

   SELECT DISTINCT TotalDue FROM [AwsDataCatalog].[sampledb].Customers 

9. Sort a result set in ascending order:
   

   SELECT Name, TotalDue FROM [AwsDataCatalog].[sampledb].Customers  ORDER BY TotalDue ASC

Aggregate Functions

For SELECT examples using aggregate functions, see Aggregate Functions.

JOIN Queries

See JOIN Queries for SELECT query examples using JOINs.

Projection Functions

See Projection Functions for SELECT examples with projection functions.

Predicate Functions

For SELECT examples using predicate functions, see Predicate Functions.