NAME
    DBIx::ThinSQL - A lightweight SQL helper for DBI

VERSION
    0.0.49 (2020-02-04) development release.

SYNOPSIS
        use strict;
        use warnings;
        use DBIx::ThinSQL qw/ bv qv /;

        my $db = DBIx::ThinSQL->connect(
            'dbi:Driver:...'
            'username',
            'password',
        );

        # Some basic CrUD statements to show the simple stuff first. Note
        # the inline binding of data that you normally have to call
        # $dbh->bind_param() on.

        my $success = $db->xdo(
            insert_into => 'actors',
            values      => {
                id    => 1,
                name  => 'John Smith',
                photo => bv( $image, DBI::SQL_BLOB ),
            },
        );

        # A "where" with a HASHref "AND"s the elements together

        my $count = $db->xdo(
            update => 'actors',
            set    => { name => 'Jack Smith' },
            where  => { id => 1, name => \'IS NOT NULL' },
        );

        # A "where" with an ARRAYref concatenates items together. Note the
        # string that is quoted according to the database type.

        my $count = $db->xdo(
            delete_from => 'actors',
            where       => [
                'actor_id = 1', ' OR ',
                'last_name != ', qv("Jones", DBI::SQL_VARCHAR ),
            ],
        );

        # Methods for reading from the database depend on the type of
        # structure you want back: arrayref or hashref references.

        my $ref = $db->xhashref(
            select => [ 'id', 'name', qv("Some string") ],
            from   => 'actors',
            where  => [
                'id = ', qv( 1, DBI::SQL_INTEGER ),
                ' AND photo IS NOT NULL',
            ],
            limit  => 1,
        );

        $db->xdo(
            insert_into => [ 'table', 'col1', 'col2', 'col3' ],
            select => [ 't1.col3', 't3.col4', bv( 'value', DBI::SQL_VARCHAR ) ],
            from   => 'table AS t1',
            inner_join => 'other_table AS t2',
            on         => 't1.something = t2.else',
            left_join  => 'third_table AS t3',
            on    => [ 't3.dont = t1.care AND t1.fob = ', qv( 1, DBI::SQL_INT ) ],
            where => [],
            order_by => [ 't3.dont', 't1.col4' ],
            limit    => 2,
        );

        $db->txn( sub {
            # Anything you like, done inside a BEGIN/COMMIT pair, with
            # nested calls to txn() done inside a SAVEPOINT/RELEASE pair.
        })

DESCRIPTION
    Sorry, this documentation is invalid or out of date.

    DBIx::ThinSQL is an extension to the Perl Database Interface (DBI).
    It is designed for complicated queries and efficient access to
    results. With an API that lets you easily write almost-raw SQL,
    DBIx::ThinSQL gives you unfettered access to the power and
    flexibility of your underlying database. It aims to be a tool for
    programmers who want their databases to work just as hard as their
    Perl scripts.

    DBIx::ThinSQL gives you access to aggregate expressions, joins,
    nested selects, unions and database-side operator invocations.
    Transactional support is provided via DBIx::Connector. Security
    conscious coders will be pleased to know that all user-supplied
    values are bound properly using DBI "bind_param()". Binding binary
    data is handled transparently across different database types.

    DBIx::ThinSQL offers a couple of very simple Create, Retrieve,
    Update and Delete (CRUD) action methods. These are designed to get
    you up and running quickly when your query data is already inside a
    hashref. The methods are abstractions of the real API, but should
    still read as much as possible like SQL.

    Although rows can be retrieved from the database as simple objects,
    DBIx::ThinSQL does not attempt to be an Object-Relational-Mapper
    (ORM). There are no auto-inflating columns or automatic joins and
    the code size and speed reflect the lack of complexity.

    DBIx::ThinSQL uses the light-weight Log::Any for logging.

CONSTRUCTOR
    Works like a normal DBI. Can be used with things like
    DBIx::Connector to get nice transaction support.

DBH METHODS
    share_dir -> Path::Tiny
        Returns the path to the distribution share directory. If
        $DBIx::ThinSQL::SHARE_DIR is set then that value will be
        returned instead of the default method which uses
        File::ShareDir.

    throw_error
        If DBIX::ThinSQL or a statement raises an exception then the
        "throw_error()" method will be called. By default it just croaks
        but classes that inherit from DBIx::ThinSQL can override it. The
        original use case was to turn database error text into blessed
        objects.

    xprepare
        Does a prepare but knows about bind values and quoted values.

    xprepare_cached
        Does a prepare_cached but knows about bind values and quoted
        values.

    xval
        Creates a statement handle using xprepare(), executes it, and
        returns the result of the val() method.

    xlist
        Creates a statement handle using xprepare(), executes it, and
        returns the result of the list() method.

    xarrayref
        Does a prepare but knows about bind values and quoted values.

    xarrayrefs
        Does a prepare but knows about bind values and quoted values.

    xhashref
        Does a prepare but knows about bind values and quoted values.

    xhashrefs
        Does a prepare but knows about bind values and quoted values.

    txn( &coderef )
        Runs the &coderef subroutine inside an SQL transaction. If
        &coderef raises an exception then the transaction is rolled back
        and the error gets re-thrown.

        Calls to "txn" can be nested. Savepoints will be used by nested
        "txn" calls for databases that support them.

    dump( $sql, [ @bind_values ] )
    xdump( @tokens )
        Debugging shortcut methods. Take either an SQL string (for
        "dump") or a set of tokens (for "xdump"), run the query, and
        then call the "dump_results" (which pretty-prints to STDOUT) on
        the resulting statement handle.

    log_debug( $sql, [ @bind_values ] )
        Like "dump" but sends the results to Log::Any "debug()".

    log_warn( $sql, [ @bind_values ] )
        Like "dump" but displays the results using Perl's "warn"
        function.

STH METHODS
    val -> SCALAR
        Return the first value of the first row as a scalar.

    list -> LIST
        Return the first row from the query as a list.

    arrayref -> ARRAYREF
        Return the first row from the query as an array reference.

    arrayrefs -> ARRAYREF
    arrayrefs -> LIST
        Update rows in the database and return the number of rows
        affected. This method is retricted to the wholesale replacement
        of column values (no database-side calculations etc). Multiple
        WHERE key/values are only 'AND'd together. An 'undef' value maps
        to SQL's NULL value.

    hashref -> HASHREF
        Delete rows from the database and return the number of rows
        affected.

    hashrefs -> ARRAYREF[HASHREF]
    hashrefs -> LIST
        Delete rows from the database and return the number of rows
        affected.

CLASS FUNCTIONS
    The following functions can be exported individually or all at once
    using the ':all' tag. They all return an object which can be
    combined with or used inside other functions.

    bv( $value, [ $bind_type ] ) -> DBIx::ThinSQL::BindValue
        This function returns an object which tells DBIx::ThinSQL to
        bind $value using a placeholder. The optional $bind_type is a
        database type (integer, varchar, timestamp, bytea, etc) which
        will be converted to the appropriate bind constant during a
        prepare() or prepare_cached() call.

    qv( $value )
    AND
    OR
    "sq ( @subquery )" -> DBIx::ThinSQL::_expr
        A function for including a sub query inside another:

            $db->xarrayref(
                select => 'subquery.col',
                from   => sq(
                    select => 'col',
                    from   => 'table',
                    where  => 'condition IS NOT NULL',
                )->as('subquery'),
            );

    sql_and( @args ) -> DBIx::ThinSQL::Expr
        Maps to "$arg1 AND $arg2 AND ...".

    sql_case( @stmts ) -> DBIx::ThinSQL::Expr
        Wraps @stmts inside a CASE/END pair while converting arguments
        to expressions where needed.

            sql_case(
                when => $actors->name->is_null,
                then => 'No Name',
                else => $actors->name,
            )->as('name')

            # CASE WHEN actors0.name IS NULL
            # THEN ? ELSE actors0.name END AS name

    sql_coalesce(@args) -> DBIx::ThinSQL::Expr
        Maps to "COALESCE($arg1, $arg2, ...)".

    sql_cast($arg1, as => $arg2) -> DBIx::ThinSQL::Expr
        Maps to "CAST( $arg1 AS $arg2 )".

    sql_concat(@args) -> DBIx::ThinSQL::Expr
        Maps to "$arg1 || $arg2 || ...".

    sql_count(@args) -> DBIx::ThinSQL::Expr
        Maps to "COUNT($arg1, $arg2, ...)".

    sql_exists(@args) -> DBIx::ThinSQL::Expr
        Maps to "EXISTS(@args)".

    sql_func('myfunc', @args) -> DBIx::ThinSQL::Expr
        Maps to "MYFUNC($arg1, $arg2, ...)".

    sql_hex(@args) -> DBIx::ThinSQL::Expr
        Maps to "HEX($arg1, $arg2, ...)".

    sql_length(@args) -> DBIx::ThinSQL::Expr
        Maps to "LENGTH(@args)".

    sql_lower(@args) -> DBIx::ThinSQL::Expr
        Maps to "LOWER(@args)".

    sql_ltrim(@args) -> DBIx::ThinSQL::Expr
        Maps to "LTRIM(@args)".

    sql_max(@args) -> DBIx::ThinSQL::Expr
        Maps to "MAX(@args)".

    sql_min(@args) -> DBIx::ThinSQL::Expr
        Maps to "MIN(@args)".

    sql_rtrim(@args) -> DBIx::ThinSQL::Expr
        Maps to "RTRIM(@args)".

    sql_sum(@args) -> DBIx::ThinSQL::Expr
        Maps to "MIN(@args)".

    sql_or(@args) -> DBIx::ThinSQL::Expr
        Maps to "$arg1 OR $arg2 OR ...".

    sql_replace(@args) -> DBIx::ThinSQL::Expr
        Maps to "REPLACE($arg1,$arg2 [,$arg3])".

    sql_substr(@args) -> DBIx::ThinSQL::Expr
        Maps to "SUBSTR($arg1, $arg2, ...)".

    sql_table($name, @columns) -> DBIx::ThinSQL::Expr
        Maps to "name(col1,col2,...)".

    sql_upper(@args) -> DBIx::ThinSQL::Expr
        Maps to "UPPER(@args)".

    sql_values(@args) -> DBIx::ThinSQL::Expr
        Maps to "VALUES($arg1, $arg2, ...)".

SEE ALSO
    Log::Any

DEVELOPMENT & SUPPORT
    DBIx::ThinSQL is managed via Github:

        https://github.com/mlawren/p5-DBIx-ThinSQL/tree/devel

    DBIx::ThinSQL follows a semantic versioning scheme:

        http://semver.org

AUTHOR
    Mark Lawrence <nomad@null.net>

COPYRIGHT AND LICENSE
    Copyright (C) 2013-2020 Mark Lawrence <nomad@null.net>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.