SELECT Statements

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 ActOn adapter:

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> ] 
  } [ , ... ]
  [ 
    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> { AND | = | < | > | >= | <= } [ <expression> ]
    } [ { AND | OR } ... ]

Examples

Return all columns:
```
SELECT * FROM Images
```
Rename a column:
```
SELECT "Name" AS MY_Name FROM Images
```

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

SELECT CAST(Size AS VARCHAR) AS Str_Size FROM Images

Search data:

SELECT * FROM Images WHERE FolderName = 'New Folder'

The ActOn APIs support the following operators in the WHERE clause: AND, =, <, >, >=, <=.
```
SELECT * FROM Images WHERE FolderName = 'New Folder';
```
Return the number of items matching the query criteria:
```
SELECT COUNT(*) AS MyCount FROM Images 
```
Return the number of unique items matching the query criteria:
```
SELECT COUNT(DISTINCT Name) FROM Images 
```
Return the unique items matching the query criteria:
```
SELECT DISTINCT Name FROM Images 
```

Sort a result set in ascending order:

SELECT Id, Name FROM Images  ORDER BY Name ASC

Aggregate Functions

For SELECT examples using aggregate functions, see Aggregate Functions.

JOIN Queries

See JOIN Queries for SELECT query examples using JOINs.

Date Literal Functions

Date Literal Functions contains SELECT examples with date literal functions.

Window Functions

See Window Functions for SELECT examples containing window functions.

Table-Valued Functions

See Table-Valued Functions for SELECT examples with table-valued functions.

TDV Adapter for Act-On