SQL SELECT

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Purpose

Retrieves data from one or more tables or views

Syntax

SELECT [ALL | DISTINCT | DISTINCTROW | TOP <expN> [PERCENT]] * | [<t_alias>|<"t_alias">.]<column>|<"column"> | <constant> | <function> | <aggregate> [[AS] <c_alias>] [,...] [, *]

FROM {OJ <"t_alias"> <table> [LEFT | RIGHT | FULL] OUTER JOIN <"t_alias"> <table2> ON <exp> = <exp>}

| [FORCE] [<database>! | <database>.]<table> | <view> [[AS] <t_alias>] [, ...]

| [FORCE] [<database>! | <database>.]<table> | <view> [[AS] <t_alias>] INNER JOIN | OUTER JOIN | LEFT [OUTER] JOIN | RIGHT [OUTER] JOIN (<nested select>) [<database>! | <database>.]<table2> ON [<database>! | <database>.]<table>.<column> = [<database>! | <database>.]<table2>.<column> [, ...] | CROSS JOIN | FULL [OUTER] JOIN [<database>! | <database>.]<table2>

| <odbc DSN>::<table>

[WHERE <condition>]

[GROUP BY <expr> | <column> | <number> [,...]]

[HAVING <condition>]

[ORDER BY <expr> | <column> | <number> [ASC | DESC] [,...]]

[LIMIT [<offset>,] <row_count> | <row_count> OFFSET <offset>]

[NOSMARTQUERY | SMARTQUERY]

[FOR UPDATE]

[INTO [,...] |

INTO ARRAY <array-name> |

INTO ARRAYOFOBJECTS <array-name> | CONSOLE | STDOUT |

INTO CURSOR <cursor-name> [NOFILTER | READWRITE] |

INTO NAME | OBJECT <object-ref> |

INTO JSON <filename> | CONSOLE |

INTO HTML <html filename> | CONSOLE |

INTO XML <xml filename> | CONSOLE |

INTO CSV <csv filename> | CONSOLE |

INTO DBF | TABLE <table-name> [DATABASE <database> [NAME <long table-name>]]

| SAVE AS [<database>! | <database>.]<table-name> | XML <xml filename> [FORMAT < RECITAL | ADO | EXCEL >]

| TO FILE <text filename> [DELIMITED] | PRINTER [PROMPT] | SCREEN

[PREFERENCE <preference>] [NOCONSOLE] [PLAIN] [NOWAIT]

[UNION [ALL] <nested select>]

See Also

AGGREGATES, CLEAR SMARTQUERY, CREATE CURSOR, CREATE TABLE, EXPLAIN, FETCH, INSERT, OPERATORS, PREDICATES, PSEUDO COLUMNS, SET SMARTQUERY, SET SQLROWID, SET XMLFORMAT, SYSTEM TABLES, UPDATE

Description

The SELECT statement is used to retrieve data from one or more tables or views. It creates a logical table from other tables. A logical table is a temporary collection of data that satisfy conditions specified in a SELECT statement. To select data you must be the owner of the table or have already been granted SELECT privileges.

If no destination is specified for the results (INTO, SAVE AS or TO), then they are saved to a cursor, a temporary table with the alias name 'cursor'. This table is automatically opened in the next empty workarea and a BROWSE is issued.


Keywords Description
ALL Returns all the selected rows including duplicates. This is the default.
DISTINCT Only returns one copy of each set of duplicate rows selected. Duplicate rows are those with matching values of each expression in the select list.
DISTINCTROW Only returns one copy of each set of duplicate rows selected. Duplicate rows are those with matching values of the entire row, not just the columns in the select list.
TOP <expN> [PERCENT] The <expN> defines the TOP number of rows to be returned from the specified select statement. The optional PERCENT keyword causes the <expN> to be used as the percentage of rows to be returned.
* Selects all columns from all tables listed in the FROM clause.
t_alias Provides a different name for the table. Other references to table name throughout the query must refer to this alias name. The t_alias can be enclosed in double-quotes if required.
column The name of the column you are selecting. The column can be enclosed in double-quotes if required.
AS Used to specify an alternative name for a table or a column
c_alias Provides a different name for the column and column heading.
constant This specifies a constant expression. See expressions for more information.
function A Lianja function that may or may not include column names. See the function references for more information.
aggregate An aggregate expression uses an aggregate function to summarize selected data from a table.
FORCE The FORCE keyword specifies that the tables are joined in the order in which they are listed in the SELECT statement.
database The name of the database to which the table belongs. The '!' or '.' character must be included between the database name and the table name.
table The table name from which to select data. When data is being selected from encrypted tables, the table reference can include the three-part encryption key, enclosed in angled brackets, appended to the table name. The SET ENCRYPTION command allows a default encryption key to be defined. If the key is not included in the <table>, this default key will be used. If the default key is not the correct key for the table, an error will be given.
view The name of a view defined with the CREATE VIEW statement
<odbc DSN>::<table> The name of a 32-bit ODBC System DSN followed by the separator '::' followed by a table name (from v5.0).
{OJ ... OUTER JOIN ...} Specifies the join type as left outer. This will return all the rows from the left table and matching rows from the right or a null row if no match is found.
{OJ ... LEFT OUTER JOIN ...} Specifies the join type as left outer. This will return all the rows from the left table and matching rows from the right or a null row if no match is found.
{OJ ... RIGHT OUTER JOIN ...} Specifies the join type as right outer. This will return all the rows from the right table and the matching rows from the left or a null row if no match is found.
{OJ ... FULL OUTER JOIN ...} Specifies the join type as full outer. This will return all the rows from both tables.
<table2> The name of the joined table in the query. When data is being selected from encrypted tables, the table2 reference can include the three-part encryption key, enclosed in angled brackets, appended to the table name. The SET ENCRYPTION command allows a default encryption key to be defined. If the key is not included in the <table2>, this default key will be used. If the default key is not the correct key for the table, an error will be given. If no default key is active, a dialog box will be displayed in Lianja to allow the user to enter the key.
ON <exp> = <exp> The expression used to JOIN the two tables together.
INNER JOIN Specifies the join type as inner. An inner join names the linking criterion used to find matches between the two tables. Only rows for which a match is found in both tables are returned.
OUTER JOIN Specifies the join type as outer. An outer join takes two tables and displays all the rows from one table and the matching rows from the other or a null row if no matches are found.
LEFT [OUTER] JOIN Specifies the join type as left outer. This will return all the rows from the left table and matching rows from the right or a null row if no match is found.
RIGHT [OUTER] JOIN Specifies the join type as right outer. This will return all the rows from the right table and the matching rows from the left or a null row if no match is found.
CROSS JOIN Specifies the join type as cross join. This will return a Cartesian product: all combinations of rows.
FULL [OUTER] JOIN Specifies the join type as full outer. This will return all the rows from both tables.
<nested select> An additional SELECT statement.
ON <table>.column = <table2>.column The expression used to JOIN the two tables together.
WHERE This restricts the rows selected to those for which the condition is TRUE. If this clause is omitted than all rows are returned. The condition can be a SELECT sub-query.
GROUP BY Groups the selected rows based on the value of an expression, the column name or number for each row and returns a single row of summary information for each group. The default, ASC, returns the data in ascending order, specifying DESC returns the data in descending order.
HAVING Restricts the groups of rows returned to those groups for which the specified condition is TRUE. If you omit this clause then all rows are returned.
ORDER BY Orders rows based on the value returned by an expression, a column name or number. The default, ASC, returns the data in ascending order, specifying DESC returns the data in descending order.
LIMIT Restricts the rows returned.
<offset> The row at which the selection will start. Rows are counted from 0.
<row_count> The maximum number of rows to be returned.
NOSMARTQUERY Ignore the SMARTQUERY cache.
SMARTQUERY Force SMARTQUERY.
FOR UPDATE Locks the selected rows.
INTO <data variable> [,...] Specify data variables to receive the data retrieved by the select statement. The select statement can only be a singleton select. The data variables will be created if they do not exist and overwritten if they do.
INTO ARRAY <array-name> Specify an array to receive the data retrieved by the select statement. The array is automatically created, so need not be pre-defined. This is a two-dimensional array of result rows.
INTO ARRAYOFOBJECTS <array-name> | CONSOLE | STDOUT Specify an array to receive the data retrieved by the select statement. The array is automatically created, so need not be pre-defined. This is a one-dimensional array with each element being an object that contains a result row. CONSOLE | STDOUT write to standard output. Supported from Lianja v2.0.0.
INTO CURSOR <cursor-name> Specify a cursor to receive the data retrieved by the select statement. This saves the data into a temporary table in a workarea. The Lianja SELECT command can be used to select the workarea for processing with Lianja commands. The NOFILTER keyword is used for creating a cursor that can be used in subsequent queries. The READWRITE keyword is used to create a temporary modifiable cursor.
INTO NAME | OBJECT <object-ref> Specify an object to receive the data retrieved by the select statement. The object is automatically created, so need not be pre-defined.
INTO JSON <filename> | CONSOLE Specify a JavaScript Object Notation filename to be created and populated with the result of the select statement, or send the JSON output to the console.
INTO HTML <html filename> | CONSOLE Specify an HTML filename to be created and populated with the result of the select statement or send the HTML output to the console.
INTO XML <xml filename> | CONSOLE Specify an XML filename to be created and populated with the result of the select statement or send the XML output to the console.
INTO CSV <csv filename> | CONSOLE Specify a CSV filename to be created and populated with the result of the select statement or send the CSV output to the console (from v5.0).
INTO DBF | TABLE <table-name> Specify a table to receive the data retrieved by the select statement. The table's database and a long name can optionally be specified using the DATABASE and NAME clauses respectively.
SAVE AS <table-name> Specify a table name to be created and populated with the result of the select statement.
SAVE AS XML <xml filename> [FORMAT < RECITAL | ADO | EXCEL >] Specify an XML filename to be created and populated with the result of the select statement. A Document Type Definition (DTD) file, used to validate the XML file, will also be created if the XML format is set to RECITAL. The default format for XML if not specified is Microsoft® ActiveX® Data Objects (ADO). This default can also be set with the command SET XMLFORMAT.
TO FILE [DELIMITED] Saves the results to the specified text file. If the DELIMITED keyword is included, the results are written out in delimited format.
TO PRINTER Sends the results to the currently defined printer. The optional PROMPT keyword is used to display a print dialog before printing.
TO SCREEN Sends the results to the main screen or active window.
PREFERENCE The PREFERENCE clause is used to save BROWSE window preferences.
NOCONSOLE The NOCONSOLE keyword is used to prevent results sent to a file or printer (TO FILE | PRINTER) also being displayed on the screen.
PLAIN The PLAIN keyword is used to disable the display of column headings.
NOWAIT The NOWAIT keyword is used to continue program execution immediately after BROWSE window display instead of when the BROWSE window is closed.
UNION [ALL] Combines the end result of the main SELECT statement with a secondary <nested select> SELECT statement. The ALL keyword specifies that duplicates should be retained.

Example

// Specifying database name
SELECT * FROM southwind!orders
// or
SELECT * FROM southwind.orders
 
// Select all rows, including duplicates, from an encrypted table
SELECT ALL * FROM enctab<key_1,key2,key_3>
 
// Select "last_name" column from rows with a unique "last_name"
SELECT DISTINCT last_name FROM customer
 
// Select "last_name" column from unique rows
SELECT DISTINCTROW last_name FROM customer
 
// Select first 10 rows
SELECT TOP 10 * FROM accounts
 
// Select first 50% of the rows
SELECT TOP 50 PERCENT * FROM accounts
 
// Crystal Reports / ODBC style JOINS: LEFT OUTER, RIGHT OUTER, FULL OUTER
SELECT customer.account_no, customer.last_name, accounts.ord_value;
  FROM {OJ "customer" customer;
  LEFT OUTER JOIN "accounts" accounts;
  ON customer.account_no = accounts.account_no}
 
SELECT customer.account_no, customer.last_name, accounts.ord_value;
  FROM {OJ "customer" customer;
  RIGHT OUTER JOIN "accounts" accounts;
  ON customer.account_no = accounts.account_no}
 
SELECT customer.account_no, customer.last_name, accounts.ord_value;
  FROM {OJ "customer" customer;
  FULL OUTER JOIN "accounts" accounts;
  ON customer.account_no = accounts.account_no}
 
// JOINS: INNER, LEFT OUTER, RIGHT OUTER, CROSS, FULL
SELECT customer.account_no, customer.last_name, accounts.ord_value;
  FROM customer;
  INNER JOIN accounts;
  ON customer.account_no = accounts.account_no
 
SELECT customer.account_no, customer.last_name, accounts.ord_value;
  FROM customer;
  LEFT OUTER JOIN accounts;
  ON customer.account_no = accounts.account_no
 
SELECT customer.account_no, customer.last_name, accounts.ord_value;
  FROM customer;
  RIGHT OUTER JOIN accounts;
  ON customer.account_no = accounts.account_no
 
SELECT customer.account_no, customer.last_name, accounts.ord_value;
  FROM customer;
  CROSS JOIN accounts
 
SELECT customer.account_no, customer.last_name, accounts.ord_value;
  FROM customer;
  FULL OUTER JOIN accounts
 
// JOINs with nested SELECTs
SELECT contactname FROM customers;
  WHERE customerid IN;
 (SELECT customerid FROM orders WHERE orderdate = {07/19/1996}) 
 
SELECT shipname FROM orders, customers;
  WHERE orders.customerid = customers.customerid AND;
  employeeid = (SELECT max(employeeid);
  FROM orders;
  WHERE orderdate = {07/19/1996});
  order by shipname
 
SELECT contactname FROM customers;
  WHERE ctod("07/19/1996") > ANY;
 (SELECT orderdate FROM orders WHERE customers.customerid = orders.customerid)
 
SELECT orders.customerid;
  FROM orders;
  WHERE 30 > ALL (SELECT sum(quantity) FROM order_details;
  WHERE orders.orderid = order_details.orderid)
 
SELECT orderid,customerid;
  FROM orders as o1;
  WHERE 2 < (SELECT quantity FROM order_details as i1;
  WHERE o1.orderid = i1.orderid AND i1.productid = 71) 
 
SELECT lastname FROM employees;
  WHERE exists;
  (SELECT * FROM orders;
  WHERE employees.employeeid = orders.employeeid;
  AND orderdate = CTOD("11/11/1996"))
 
SELECT lastname FROM employees;
  WHERE not exists;
  (SELECT * FROM orders;
  WHERE employees.employeeid = orders.employeeid;
  AND orderdate = CTOD("11/11/1996"))
 
SELECT companyname, (select MAX(orderid);
  FROM orders as o1;
  WHERE o1.customerid = c1.customerid);
  FROM customers as c1
 
// Multiple JOINs
SELECT customer.account_no, customer.state,;
  state.descript, accounts.ord_value;
  FROM customer RIGHT OUTER JOIN accounts;
  ON customer.account_no = accounts.account_no,;
  customer INNER JOIN state;
  ON customer.state = state.state;
  ORDER BY account_no
 
// Select account number and order value details for Massachusetts customers 
SELECT account_no, ord_value;
  FROM accounts;
  WHERE account_no in (SELECT account_no FROM customer WHERE state = 'MA');
  ORDER BY account_no
 
// Select all overdue accounts with 15% commission in sorted "last_name" order.
SELECT last_name, zip, balance, balance*1.15;
  FROM customer;
  WHERE balance > 0;
  ORDER BY last_name
 
// Select total and average balance for all overdue accounts, grouped by "limit"
SELECT SUM(balance), AVG(balance);
  FROM customer;
  WHERE balance > 0;
  GROUP BY limit
 
// Select total and average balance for all overdue accounts, grouped by "limit" with column aliases
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  GROUP BY limit
 
// Select total and average balance for all overdue accounts, grouped by "limit" with column aliases
// For Massachusetts customers only
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  GROUP BY limit;
  HAVING state = "MA"
 
// Save into an array
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO ARRAY temp
 
// Save into an array of objects
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO ARRAYOFOBJECTS temp
// convert first selected row to JSON
cjson = json_encode(temp[1])
 
// Save into an object
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO object temp
 
// Save into a JSON file
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO JSON temp
 
// Save into an HTML file
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO HTML temp
 
// Save into an XML file
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO XML temp
 
// Create a cursor
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO CURSOR temp
 
// Save as a table
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO TABLE temp DATABASE mydbc
 
//or
 
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  SAVE AS temp
 
// Save in Microsoft® ActiveX® Data Objects XML format
// Any XML files created in the ADO format can be loaded
// with the Open method of the ADO Recordset object. 
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  SAVE AS XML temp.xml FORMAT ADO
// In Visual Basic the file can then be loaded:
// Set adoPrimaryRS = New Recordset
// adoPrimaryRS.Open "temp.xml"
 
// Save in Microsoft® Excel XML format
SELECT * FROM customers SAVE AS xml mycustomers.xml FORMAT EXCEL
Lianja.showDocument("mycustomers.xml")
 
// Save in text file format
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  TO FILE temp.txt
 
// Select all customer accounts that have an outstanding balance or are based in Massachusetts
SELECT account_no;
  FROM customer;
  WHERE state = 'MA';
  UNION SELECT account_no;
  FROM accounts;
  WHERE balance > 0;
  ORDER BY account_no
 
// Select a maximum of 10 rows, starting from row 6
SELECT * FROM customer;
  LIMIT 5,10
//or
SELECT * FROM customer;
  LIMIT 10 OFFSET 5
 
// Ignore the smartquery cache
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO CURSOR temp;
  nosmartquery
 
// Force smartquery
SELECT SUM(balance) AS Total, AVG(balance) AS Average;
  FROM customer;
  WHERE balance > 0;
  INTO CURSOR temp;
  smartquery