helpers.go

package clickhouse

import (
	"errors"
	"fmt"
	"net/url"
	"strings"
)

type (
	// Column name
	Column string
	// Columns array, order is important
	Columns []string
	// Row value
	Row []interface{}
	// Rows array or values
	Rows              []Row
	Array             []interface{}
	VisitParamsString map[string]interface{}
	StringArray       []string
)

// NewQuery creates new query from query string and args
func NewQuery(stmt string, args ...interface{}) Query {
	return Query{
		Stmt:   stmt,
		args:   args,
		params: url.Values{},
	}
}

// BuildInsert create new query from columns and one row
func BuildInsert(tbl string, cols Columns, row Row) (Query, error) {
	return BuildMultiInsert(tbl, cols, Rows{row})
}

// BuildMultiInsert create new bulk query from columns and rows
func BuildMultiInsert(tbl string, cols Columns, rows Rows) (Query, error) {
	var (
		stmt string
		args []interface{}
	)

	if len(cols) == 0 || len(rows) == 0 {
		return Query{}, errors.New("rows and cols cannot be empty")
	}

	colCount := len(cols)
	rowCount := len(rows)
	args = make([]interface{}, colCount*rowCount)
	argi := 0

	for _, row := range rows {
		if len(row) != colCount {
			return Query{}, errors.New("Amount of row items does not match column count")
		}
		for _, val := range row {
			args[argi] = val
			argi++
		}
	}

	binds := strings.Repeat(":value:,", colCount)
	binds = "(" + binds[:len(binds)-1] + "),"
	batch := strings.Repeat(binds, rowCount)
	batch = batch[:len(batch)-1]

	stmt = fmt.Sprintf("INSERT INTO %s (%s) VALUES %s", tbl, strings.Join(cols, ","), batch)

	return NewQuery(stmt, args...), nil
}