106 lines
2.3 KiB
Go
106 lines
2.3 KiB
Go
// Copyright (C) 2017 ScyllaDB
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// Use of this source code is governed by a ALv2-style
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// license that can be found in the LICENSE file.
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package qb
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// UPDATE reference:
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// https://cassandra.apache.org/doc/latest/cql/dml.html#update
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import (
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"bytes"
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)
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// UpdateBuilder builds CQL UPDATE statements.
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type UpdateBuilder struct {
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table string
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using using
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columns columns
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where where
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_if _if
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exists bool
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}
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// Update returns a new UpdateBuilder with the given table name.
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func Update(table string) *UpdateBuilder {
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return &UpdateBuilder{
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table: table,
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}
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}
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// ToCql builds the query into a CQL string and named args.
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func (b *UpdateBuilder) ToCql() (stmt string, names []string) {
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cql := bytes.Buffer{}
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cql.WriteString("UPDATE ")
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cql.WriteString(b.table)
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cql.WriteByte(' ')
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names = append(names, b.using.writeCql(&cql)...)
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cql.WriteString("SET ")
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for i, c := range b.columns {
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cql.WriteString(c)
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cql.WriteString("=?")
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if i < len(b.columns)-1 {
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cql.WriteByte(',')
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}
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}
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names = append(names, b.columns...)
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cql.WriteByte(' ')
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names = append(names, b.where.writeCql(&cql)...)
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names = append(names, b._if.writeCql(&cql)...)
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if b.exists {
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cql.WriteString("IF EXISTS ")
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}
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stmt = cql.String()
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return
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}
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// Table sets the table to be updated.
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func (b *UpdateBuilder) Table(table string) *UpdateBuilder {
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b.table = table
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return b
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}
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// Timestamp sets a USING TIMESTAMP clause on the query.
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func (b *UpdateBuilder) Timestamp() *UpdateBuilder {
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b.using.timestamp = true
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return b
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}
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// TTL sets a USING TTL clause on the query.
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func (b *UpdateBuilder) TTL() *UpdateBuilder {
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b.using.ttl = true
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return b
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}
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// Set adds SET clauses to the query.
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func (b *UpdateBuilder) Set(columns ...string) *UpdateBuilder {
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b.columns = append(b.columns, columns...)
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return b
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}
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// Where adds an expression to the WHERE clause of the query. Expressions are
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// ANDed together in the generated CQL.
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func (b *UpdateBuilder) Where(w ...Cmp) *UpdateBuilder {
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b.where = append(b.where, w...)
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return b
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}
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// If adds an expression to the IF clause of the query. Expressions are ANDed
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// together in the generated CQL.
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func (b *UpdateBuilder) If(w ...Cmp) *UpdateBuilder {
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b._if = append(b._if, w...)
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return b
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}
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// Existing sets a IF EXISTS clause on the query.
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func (b *UpdateBuilder) Existing() *UpdateBuilder {
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b.exists = true
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return b
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}
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