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 SQL engine of the driver:

SELECT {
  [ TOP <numeric_literal> | DISTINCT ]
  { 
    * 
    | { 
        <expression> [ [ AS ] <column_reference> ] 
        | { <table_name> | <correlation_name> } .* 
      } [ , ... ] 
  }
  [ INTO csv:// [ filename= ] <file_path> [ ;delimiter=tab ] ]
  { 
    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> 
    ]
  ] 
} | SCOPE_IDENTITY() 

<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 | AND | OR | CONTAINS | BETWEEN } [ <expression> ]
  } [ { AND | OR } ... ] 

Examples

1. Return all columns:
   

   SELECT * FROM Account

2. Rename a column:
   

   SELECT [Name] AS MY_Name FROM Account

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

   SELECT CAST(AnnualRevenue AS VARCHAR) AS Str_AnnualRevenue FROM Account

4. Search data:
   

   SELECT * FROM Account WHERE FirstName <> 'Bob'

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

   SELECT * FROM Account WHERE FirstName <> 'Bob';

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

   SELECT COUNT(*) AS MyCount FROM Account 

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

   SELECT COUNT(DISTINCT Name) FROM Account 

8. Return the unique items matching the query criteria:
   

   SELECT DISTINCT Name FROM Account 

9. Summarize data:
   

   SELECT Name, MAX(AnnualRevenue) FROM Account GROUP BY Name

   See Aggregate Functions for details.
10. Retrieve data from multiple tables.
    

    SELECT i.Amount, c.CustomerName FROM Invoices i, Customers c WHERE i.CustomerName = c.CustomerName

    See JOIN Queries for details.
11. Sort a result set in ascending order:
    

    SELECT Id, Name FROM Account  ORDER BY Name ASC

12. Restrict a result set to the specified number of rows:
    

    SELECT Id, Name FROM Account LIMIT 10 

13. Parameterize a query to pass in inputs at execution time. This enables you to create prepared statements and mitigate SQL injection attacks.
    

    SELECT * FROM Account WHERE FirstName = @param

See Explicitly Caching Data for information on using the SELECT statement in offline mode.

Pseudo Columns

Some input-only fields are available in SELECT statements. These fields, called pseudo columns, do not appear as regular columns in the results, yet may be specified as part of the WHERE clause. You can use pseudo columns to access additional features from Amazon DynamoDB.

    SELECT * FROM Account WHERE ReturnConsumedCapacity = '@ReturnConsumedCapacity'