knex/lib/dialects/mssql/query/compiler.js
2015-12-08 11:37:31 -06:00

100 lines
3.0 KiB
JavaScript

// MSSQL Query Compiler
// ------
'use strict';
var inherits = require('inherits');
var QueryCompiler = require('../../../query/compiler');
var assign = require('lodash/object/assign');
function QueryCompiler_MSSQL(client, builder) {
QueryCompiler.call(this, client, builder);
}
inherits(QueryCompiler_MSSQL, QueryCompiler);
assign(QueryCompiler_MSSQL.prototype, {
_emptyInsertValue: '() values ()',
// Update method, including joins, wheres, order & limits.
update: function update() {
var join = this.join();
var updates = this._prepUpdate(this.single.update);
var where = this.where();
var order = this.order();
var limit = this.limit_();
return 'update ' + (limit ? limit + ' ' : '') + this.tableName + (join ? ' ' + join : '') + ' set ' + updates.join(', ') + (where ? ' ' + where : '') + (order ? ' ' + order : '');
},
// Compiles the columns in the query, specifying if an item was distinct.
columns: function columns() {
var distinct = false;
if (this.onlyUnions()) return '';
var columns = this.grouped.columns || [];
var i = -1,
sql = [];
if (columns) {
while (++i < columns.length) {
var stmt = columns[i];
if (stmt.distinct) distinct = true;
if (stmt.type === 'aggregate') {
sql.push(this.aggregate(stmt));
} else if (stmt.value && stmt.value.length > 0) {
sql.push(this.formatter.columnize(stmt.value));
}
}
}
if (sql.length === 0) sql = ['*'];
var limit = this.limit_();
return 'select ' + (distinct ? 'distinct ' : '') + (limit ? limit + ' ' : '') + sql.join(', ') + (this.tableName ? ' from ' + this.tableName : '');
},
// Compiles a `truncate` query.
truncate: function truncate() {
return 'truncate table ' + this.tableName;
},
forUpdate: function forUpdate() {
return 'with (READCOMMITTEDLOCK)';
},
forShare: function forShare() {
return 'with (NOLOCK)';
},
// Compiles a `columnInfo` query.
columnInfo: function columnInfo() {
var column = this.single.columnInfo;
return {
sql: 'select * from information_schema.columns where table_name = ? and table_schema = ?',
bindings: [this.single.table, this.client.database()],
output: function output(resp) {
var out = resp.reduce(function (columns, val) {
columns[val.COLUMN_NAME] = {
defaultValue: val.COLUMN_DEFAULT,
type: val.DATA_TYPE,
maxLength: val.CHARACTER_MAXIMUM_LENGTH,
nullable: val.IS_NULLABLE === 'YES'
};
return columns;
}, {});
return column && out[column] || out;
}
};
},
limit_: function limit_() {
var noLimit = !this.single.limit && this.single.limit !== 0;
if (noLimit) return '';
return 'top (' + this.formatter.parameter(this.single.limit) + ')';
},
limit: function limit() {
return '';
}
});
// Set the QueryBuilder & QueryCompiler on the client object,
// incase anyone wants to modify things to suit their own purposes.
module.exports = QueryCompiler_MSSQL;