knex/lib/dialects/sqlite3/query/compiler.js

107 lines
3.3 KiB
JavaScript

'use strict';
// SQLite3 Query Builder & Compiler
var _ = require('lodash')
var inherits = require('inherits')
var Raw = require('../../../raw')
var QueryCompiler = require('../../../query/compiler')
var assign = require('lodash/object/assign');
function QueryCompiler_SQLite3(client, builder) {
QueryCompiler.call(this, client, builder)
}
inherits(QueryCompiler_SQLite3, QueryCompiler)
assign(QueryCompiler_SQLite3.prototype, {
// The locks are not applicable in SQLite3
forShare: emptyStr,
forUpdate: emptyStr,
// 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.
insert: function() {
var insert = this.single.insert
var sql = 'insert into ' + this.tableName + ' '
if (_.isArray(insert) && (insert.length === 1) && _.isEmpty(insert[0])) {
insert = []
}
if (_.isEmpty(insert) && !_.isFunction(insert)) {
return sql + 'default values'
}
var insertData = this._prepInsert(insert)
if (_.isString(insertData)) return sql + insertData
sql += '(' + this.formatter.columnize(insertData.columns) + ')'
if (insertData.values.length === 1) {
return sql + ' values (' + this.formatter.parameterize(insertData.values[0]) + ')'
}
var blocks = []
var i = -1
while (++i < insertData.values.length) {
var block = blocks[i] = []
var current = insertData.values[i]
for (var i2 = 0, l2 = insertData.columns.length; i2 < l2; i2++) {
block.push(this.formatter.parameter(current[i2]) + ' as ' + this.formatter.wrap(insertData.columns[i2]))
}
blocks[i] = block.join(', ')
}
return sql + ' select ' + blocks.join(' union all select ')
},
// Compile a truncate table statement into SQL.
truncate: function() {
var table = this.tableName
return {
sql: 'delete from sqlite_sequence where name = ' + this.tableName,
output: function() {
return this.query({sql: 'delete from ' + table})
}
}
},
// Compiles a `columnInfo` query
columnInfo: function() {
var column = this.single.columnInfo
return {
sql: 'PRAGMA table_info(' + this.single.table +')',
output: function(resp) {
var maxLengthRegex = /.*\((\d+)\)/
var out = _.reduce(resp, function (columns, val) {
var type = val.type
var maxLength = (maxLength = type.match(maxLengthRegex)) && maxLength[1]
type = maxLength ? type.split('(')[0] : type
columns[val.name] = {
type: type.toLowerCase(),
maxLength: maxLength,
nullable: !val.notnull,
defaultValue: val.dflt_value
}
return columns
}, {})
return column && out[column] || out
}
}
},
limit: function() {
var noLimit = !this.single.limit && this.single.limit !== 0
if (noLimit && !this.single.offset) return ''
// Workaround for offset only,
// see http://stackoverflow.com/questions/10491492/sqllite-with-skip-offset-only-not-limit
return 'limit ' + this.formatter.parameter(noLimit ? -1 : this.single.limit)
}
})
function emptyStr() {
return ''
}
module.exports = QueryCompiler_SQLite3