Default Supported SQL syntax - Summary

   CALL <function>
   CREATE [TEMP] TABLE <table> <column_def_clause>
   CREATE [TEMP] TABLE <table> AS <select statement>
   CREATE [TEMP] TABLE <table> AS IMPORT()
   CREATE FUNCTION <user_defined_function> [ NAME <perl_subroutine> ]
   CREATE KEYWORD  <user_defined_keyword>  [ NAME <perl_subroutine> ]
   CREATE OPERATOR <user_defined_operator> [ NAME <perl_subroutine> ]
   CREATE TYPE     <user_defined_type>     [ NAME <perl_subroutine> ]
   DELETE FROM <table> [<where_clause>]
   DROP TABLE [IF EXISTS] <table>
   DROP FUNCTION <function>
   DROP KEYWORD  <keyword>
   DROP OPERATOR <operator>
   DROP TYPE     <type>
   INSERT [INTO] <table> [<column_list>] VALUES <value_list>
   LOAD <user_defined_functions_module>
   SELECT <function>
   SELECT <select_clause>
          <from_clause>
          [<where_clause>]
          [ ORDER BY ocol1 [ASC|DESC], ... ocolN [ASC|DESC]] ]
          [ GROUP BY gcol1 [, ... gcolN] ]
          [ LIMIT [start,] length ]
   UPDATE <table> SET <set_clause> [<where_clause>]

Explicit Join Qualifiers

   NATURAL, INNER, OUTER, LEFT, RIGHT, FULL

Built-in Functions

   * Aggregate : MIN, MAX, AVG, SUM, COUNT
   * Date/Time : CURRENT_DATE, CURDATE, CURRENT_TIME, CURTIME, CURRENT_TIMESTAMP, NOW,
                 UNIX_TIMESTAMP
   * String    : ASCII, CHAR, BIT_LENGTH, CHARACTER_LENGTH, CHAR_LENGTH, COALESCE,
                 NVL, IFNULL, CONV, CONCAT, DECODE, HEX, OCT, BIN, INSERT, LEFT, RIGHT,
                 LOCATE, POSITION, LOWER, UPPER, LCASE, UCASE, LTRIM, RTRIM, OCTET_LENGTH,
                 REGEX, REPEAT, REPLACE, SOUNDEX, SPACE, SUBSTITUTE, SUBSTRING, SUBSTR,
                 TRANSLATE, TRIM, UNHEX
   * Numeric   : ABS, CEILING, CEIL, FLOOR, ROUND, EXP, LOG, LN, LOG10, MOD, POWER,
                 RAND, SIGN, SQRT, TRUNCATE, TRUNC
   * Trig      : ACOS, ACOSEC, ACOSECH, ACOSH, ACOT, ACOTAN, ACOTANH, ACOTH, ACSC,
                 ACSCH, ASEC, ASECH, ASIN, ASINH, ATAN, ATAN2, ATANH, COS, COSEC,
                 COSECH, COSH, COT, COTAN, COTANH, COTH, CSC, CSCH, DEG2DEG, DEG2GRAD,
                 DEG2RAD, DEGREES, GRAD2DEG, GRAD2GRAD, GRAD2RAD, PI, RAD2DEG, RAD2GRAD,
                 RAD2RAD, RADIANS, SEC, SECH, SIN, SINH, TAN, TANH
   * System    : DBNAME, USERNAME, USER

Special Utility Functions

  * IMPORT  - imports a table from an external RDBMS or perl structure
  * RUN     - prepares and executes statements in a file of SQL statements

Operators and Predicates

   = , <> , < , > , <= , >= , IS [NOT] (NULL|TRUE|FALSE) , LIKE , CLIKE , IN , BETWEEN

Identifiers and Aliases

   * regular identifiers are case insensitive (though see note on table names)
   * delimited identifiers (inside double quotes) are case sensitive
   * column and table aliases are supported

Concatenation

   * use either ANSI SQL || or the CONCAT() function
   * e.g. these are the same:  {foo || bar} {CONCAT(foo,bar)}

Comments

   * comments must occur before or after statements, cannot be embedded
   * SQL-style single line -- and C-style multi-line /* */ comments are supported

NULLs

   * currently NULLs and empty strings are identical in non-ANSI dialect.
   * use {col IS NULL} to find NULLs, not {col=''} (though both may work depending on dialect)

See below for further details.

Syntax - Details

Creates permanent and in-memory tables.

 CREATE [TEMP] TABLE <table_name> ( <column_definitions> )
 CREATE [TEMP] TABLE <table_name> AS <select statement>
 CREATE [TEMP] TABLE <table_name> AS IMPORT()

Column definitions are standard SQL column names, types, and constraints, see "Column Definitions".

  # create a permanent table
  #
  $dbh->do("CREATE TABLE qux (id INT PRIMARY KEY,word VARCHAR(30))");

The "AS SELECT" clause creates and populates the new table using the data and column structure specified in the select statement.

  # create and populate a table from a query to two other tables
  #
  $dbh->do("CREATE TABLE qux AS SELECT id,word FROM foo NATURAL JOIN bar");

If the optional keyword TEMP (or its synonym TEMPORARY) is used, the table will be an in-memory table, available for the life of the current database handle or until a DROP TABLE command is issued.

  # create a temporary table
  #
  $dbh->do("CREATE TEMP TABLE qux (id INT PRIMARY KEY,word VARCHAR(30))");

TEMP tables can be modified with SQL commands but the updates are not automatically reflected back to any permanent tables they may be associated with. To save a TEMP table - just use an AS SELECT clause:

 $dbh = DBI->connect( 'dbi:CSV:' );
 $dbh->do("CREATE TEMP TABLE qux_temp AS (id INT, word VARCHAR(30))");
 #
 # ... modify qux_temp with INSERT, UPDATE, DELETE statements, then save it
 #
 $dbh->do("CREATE TABLE qux_permanent AS SELECT * FROM qux_temp");

Tables, both temporary and permanent may also be created directly from perl arrayrefs and from heterogeneous queries to any DBI accessible data source, see the IMPORT() function.

 CREATE [ {LOCAL|GLOBAL} TEMPORARY ] TABLE $table
        (
           $col_1 $col_type1 $col_constraints1,
           ...,
           $col_N $col_typeN $col_constraintsN,
        )
        [ ON COMMIT {DELETE|PRESERVE} ROWS ]

     * col_type must be a valid data type as defined in the
       "valid_data_types" section of the dialect file for the
       current dialect

     * col_constraints may be "PRIMARY KEY" or one or both of
       "UNIQUE" and/or "NOT NULL"

     * IMPORTANT NOTE: temporary tables, data types and column
       constraints are checked for syntax violations but are
       currently otherwise *IGNORED* -- they are recognized by
       the parser, but not by the execution engine

     * The following valid ANSI SQL92 options are not currently
       supported: table constraints, named constraints, check
       constraints, reference constraints, constraint
       attributes, collations, default clauses, domain names as
       data types

DROP TABLE

 DROP TABLE $table [ RESTRICT | CASCADE ]

     * IMPORTANT NOTE: drop behavior (cascade or restrict) is
       checked for valid syntax but is otherwise *IGNORED* -- it
       is recognized by the parser, but not by the execution
       engine

INSERT INTO

 INSERT INTO $table [ ( $col1, ..., $colN ) ] VALUES ( $val1, ... $valN )

     * default values are not currently supported
     * inserting from a subquery is not currently supported

DELETE FROM

 DELETE FROM $table [ WHERE search_condition ]

     * see "search_condition" below

UPDATE

 UPDATE $table SET $col1 = $val1, ... $colN = $valN [ WHERE search_condition ]

     * default values are not currently supported
     * see "search_condition" below

SELECT

      SELECT select_clause
        FROM from_clause
     [ WHERE search_condition ]
  [ ORDER BY $ocol1 [ASC|DESC], ... $ocolN [ASC|DESC] ]
     [ LIMIT [start,] length ]

      * select clause ::=
             [DISTINCT|ALL] *
           | [DISTINCT|ALL] col1 [,col2, ... colN]
           | set_function1 [,set_function2, ... set_functionN]

      * set function ::=
             COUNT ( [ALL] * )
           | COUNT | MIN | MAX | AVG | SUM ( [DISTINCT|ALL] col_name )

      * from clause ::=
             table1 [, table2, ... tableN]
           | table1 NATURAL [join_type] JOIN table2
           | table1 [join_type] table2 USING (col1,col2, ... colN)
           | table1 [join_type] JOIN table2 ON table1.colA = table2.colB

      * join type ::=
             INNER
           | [OUTER] LEFT | RIGHT | FULL

      * if join_type is not specified, INNER is the default
      * if DISTINCT or ALL is not specified, ALL is the default
      * if start position is omitted from LIMIT clause, position 0 is
        the default
      * ON clauses may only contain equal comparisons and AND combiners
      * self-joins are not currently supported
      * if implicit joins are used, the WHERE clause must contain
        an equijoin condition for each table
      * multiple ANSI joins are not supported; use implicit joins for these
      * this also means that combinations of INNER and non-INNER joins are
        not supported

SEARCH CONDITION

       [NOT] $val1 $op1 $val1 [ ... AND|OR $valN $opN $valN ]

OPERATORS

       $op  = |  <> |  < | > | <= | >=
              | IS [NOT] NULL | IS [NOT] TRUE | IS [NOT] FALSE
              | LIKE | CLIKE | BETWEEN | IN

  The "CLIKE" operator works exactly the same as the "LIKE"
  operator, but is case insensitive.  For example:

      WHERE foo LIKE 'bar%'   # succeeds if foo is "barbaz"
                              # fails if foo is "BARBAZ" or "Barbaz"

      WHERE foo CLIKE 'bar%'  # succeeds for "barbaz", "Barbaz", and "BARBAZ"

BUILT-IN AND USER-DEFINED FUNCTIONS

There are many built-in functions and you can also create your own new functions from perl subroutines. See SQL::Statement::Functions for documentation of functions.

Identifiers (table & column names)

Regular identifiers (table and column names *without* quotes around them) are case INSENSITIVE so column foo, fOo, FOO all refer to the same column. Internally they are used in their lower case representation, so do not rely on SQL::Statement retaining your case.

Delimited identifiers (table and column names *with* quotes around them) are case SENSITIVE so column "foo", "fOo", "FOO" each refer to different columns.

A delimited identifier is *never* equal to a regular identifier (so "foo" and foo are two different columns). But do not do that :-).

Remember thought that, in DBD::CSV if table names are used directly as file names, the case sensitivity depends on the OS e.g. on Windows files named foo, FOO, and fOo are the same as each other while on Unix they are different.

Special Utility SQL Functions

IMPORT()

Imports the data and structure of a table from an external data source into a permanent or temporary table.

 $dbh->do("CREATE TABLE qux AS IMPORT(?)",{},$oracle_sth);

 $dbh->do("CREATE TABLE qux AS IMPORT(?)",{},$AoA);

 $dbh->do("CREATE TABLE qux AS IMPORT(?)",{},$AoH);

IMPORT() can also be used anywhere that table_names can:

 $sth=$dbh->prepare("
    SELECT * FROM IMPORT(?) AS T1 NATURAL JOIN IMPORT(?) AS T2 WHERE T1.id ...
 ");
 $sth->execute( $pg_sth, $mysql_sth );

The IMPORT() function imports the data and structure of a table from an external data source. The IMPORT() function is always used with a placeholder parameter which may be 1) a prepared and executed statement handle for any DBI accessible data source; or 2) an AoA whose first row is column names and whose succeeding rows are data 3) an AoH.

The IMPORT() function may be used in the AS clause of a CREATE statement, and in the FROM clause of any statement. When used in a FROM clause, it should be used with a column alias e.g. SELECT * FROM IMPORT(?) AS TableA WHERE ...

You can also write your own IMPORT() functions to treat anything as a data source. See User-Defined Function in SQL::Statement::Functions.

Examples:

 # create a CSV file from an Oracle query
 #
 $dbh = DBI->connect('dbi:CSV:');
 $oracle_sth = $oracle_dbh->prepare($any_oracle_query);
 $oracle_sth->execute(@params);
 $dbh->do("CREATE TABLE qux AS IMPORT(?)",{},$oracle_sth);

 # create an in-memory table from an AoA
 #
 $dbh      = DBI->connect( 'dbi:File:' );
 $arrayref = [['id','word'],[1,'foo'],[2,'bar'],];
 $dbh->do("CREATE TEMP TABLE qux AS IMPORT(?)",{},$arrayref);

 # query a join of a PostgreSQL table and a MySQL table
 #
 $dbh        = DBI->connect( 'dbi:File:' );
 $pg_dbh     = DBI->connect( ... DBD::pg connect params );
 $mysql_dbh  = DBI->connect( ... DBD::mysql connect params );
 $pg_sth     = $pg_dbh->prepare( ... any pg query );
 $pg_sth     = $pg_dbh->prepare( ... any mysql query );
 #
 $sth=$dbh->prepare("
    SELECT * FROM IMPORT(?) AS T1 NATURAL JOIN IMPORT(?) AS T2
 ");
 $sth->execute( $pg_sth, $mysql_sth );

RUN()

Run SQL statements from a user supplied file. Please Note: this function is experimental, please let me know if you have problems.

 RUN( sql_file )

If the file contains non-SELECT statements such as CREATE and INSERT, use the RUN() function with $dbh->do(). For example, this prepares and executes all of the SQL statements in a file called "populate.sql":

 $dbh->do(" CALL RUN( 'populate.sql') ");

If the file contains SELECT statements, the RUN() function may be used anywhere a table name may be used, for example, if you have a file called "query.sql" containing "SELECT * FROM Employee", then these two lines are exactly the same:

 my $sth = $dbh->prepare(" SELECT * FROM Employee ");

 my $sth = $dbh->prepare(" SELECT * FROM RUN( 'query.sql' ) ");

If the file contains a statement with placeholders, the values for the placeholders can be passed in the call to $sth->execute() as normal. If the query.sql file contains "SELECT id,name FROM x WHERE id=?", then these two are the same:

 my $sth = $dbh->prepare(" SELECT id,name FROM x WHERE id=?");
 $sth->execute(64);

 my $sth = $dbh->prepare(" SELECT * FROM RUN( 'query.sql' ) ");
 $sth->execute(64);

Note This function assumes that the SQL statements in the file are separated by a semi-colon+newline combination (/;\n/). If you wish to use different separators or import SQL from a different source, just override the RUN() function with your own user-defined-function.

Further details

Integers

Reals

Syntax obvious

Strings

Surrounded by either single quotes; some characters need to be escaped with a backslash, in particular the backslash itself (\\), the NULL byte (\0), Line feeds (\n), Carriage return (\r), and the quotes (\').

Note: Quoting "Strings" using double quotes are recognized as quoted identifiers (column or table names).

Parameters

Parameters represent scalar values, like Integers, Reals and Strings do. However, their values are read inside Execute() and not inside Prepare(). Parameters are represented by question marks (?).

Identifiers

Identifiers are table or column names. Syntactically they consist of alphabetic characters, followed by an arbitrary number of alphanumeric characters. Identifiers like SELECT, INSERT, INTO, ORDER, BY, WHERE, ... are forbidden and reserved for other tokens. Identifiers are always compared case-insensitively, i.e. "select foo from bar" will be evaluated the same as "SELECT FOO FROM BAR" ("FOO" will be evaluated as "foo", similar for "BAR").

Since SQL::Statement is internally using lower cased identifiers (unquoted), everytime a wildcard is used, the delivered names of the identifiers are lower cased.