knex/clients/base/sqlite3/grammar.js

// SQLite3 Grammar
// -------
(function(define) {

"use strict";

// The SQLite3 base is a bit different than the other clients,
// in that it may be run on both the client and server. So add another
// layer to the prototype chain.
define(function(require, exports) {

  var _           = require('lodash');
  var Helpers     = require('../../../lib/helpers').Helpers;
  var baseGrammar = require('../grammar').baseGrammar;

  // Extends the standard sql grammar, with any SQLite specific
  // dialect oddities.
  exports.grammar = _.defaults({

    // The keyword identifier wrapper format.
    wrapValue: function(value) {
      return (value !== '*' ? Helpers.format('"%s"', value) : "*");
    },

    // Compile the "order by" portions of the query.
    compileOrders: function(qb, orders) {
      if (orders.length === 0) return;
      return "order by " + orders.map(function(order) {
        return this.wrap(order.column) + " collate nocase " + order.direction;
      }, this).join(', ');
    },

    // Compile an insert statement into SQL.
    compileInsert: function(qb) {
      var values  = qb.values;
      var table   = this.wrapTable(qb.table);
      var columns = _.pluck(values[0], 0);

      // If there are any "where" clauses, we need to omit
      // any bindings that may have been associated with them.
      if (qb.wheres.length > 0) this.clearWhereBindings(qb);

      // If there is only one record being inserted, we will just use the usual query
      // grammar insert builder because no special syntax is needed for the single
      // row inserts in SQLite. However, if there are multiples, we'll continue.
      if (values.length === 1) {
        var sql = 'insert into ' + table + ' ';
        if (columns.length === 0) {
          sql += 'default values';
        } else {
          sql += "(" + this.columnize(columns) + ") values " + "(" + this.parameterize(_.pluck(values[0], 1)) + ")";
        }
        return sql;
      }

      var blocks = [];

      // SQLite requires us to build the multi-row insert as a listing of select with
      // unions joining them together. So we'll build out this list of columns and
      // then join them all together with select unions to complete the queries.
      for (var i = 0, l = columns.length; i < l; i++) {
        blocks.push('? as ' + this.wrap(columns[i]));
      }

      var joinedColumns = blocks.join(', ');
      blocks = [];
      for (i = 0, l = values.length; i < l; i++) {
        blocks.push(joinedColumns);
      }

      return "insert into " + table + " (" + this.columnize(columns) + ") select " + blocks.join(' union all select ');
    },

    // Compile a truncate table statement into SQL.
    compileTruncate: function (qb) {
      var sql = [];
      var table = this.wrapTable(qb.table);
      sql.push('delete from sqlite_sequence where name = ' + table);
      sql.push('delete from ' + table);
      return sql;
    },

    // For share and for update are not available in sqlite3.
    compileForUpdate: function() {},
    compileForShare:  function() {}

  }, baseGrammar);

});

})(
  typeof define === 'function' && define.amd ? define : function (factory) { factory(require, exports, module); }
);