|
| 1 | +// Copyright 2025 Dolthub, Inc. |
| 2 | +// |
| 3 | +// Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | +// you may not use this file except in compliance with the License. |
| 5 | +// You may obtain a copy of the License at |
| 6 | +// |
| 7 | +// http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | +// |
| 9 | +// Unless required by applicable law or agreed to in writing, software |
| 10 | +// distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | +// See the License for the specific language governing permissions and |
| 13 | +// limitations under the License. |
| 14 | + |
| 15 | +package window |
| 16 | + |
| 17 | +import ( |
| 18 | + "strings" |
| 19 | + |
| 20 | + "github.com/dolthub/go-mysql-server/sql" |
| 21 | + "github.com/dolthub/go-mysql-server/sql/expression/function/aggregation" |
| 22 | + "github.com/dolthub/go-mysql-server/sql/types" |
| 23 | +) |
| 24 | + |
| 25 | +type NTile struct { |
| 26 | + pos uint64 |
| 27 | + count uint64 |
| 28 | + |
| 29 | + bucketExpr sql.Expression |
| 30 | + bucketSize uint64 |
| 31 | + |
| 32 | + id sql.ColumnId |
| 33 | + window *sql.WindowDefinition |
| 34 | +} |
| 35 | + |
| 36 | +var _ sql.FunctionExpression = (*NTile)(nil) |
| 37 | +var _ sql.WindowAggregation = (*NTile)(nil) |
| 38 | +var _ sql.WindowAdaptableExpression = (*NTile)(nil) |
| 39 | +var _ sql.CollationCoercible = (*NTile)(nil) |
| 40 | + |
| 41 | +func NewNTile(expr sql.Expression) sql.Expression { |
| 42 | + return &NTile{ |
| 43 | + bucketExpr: expr, |
| 44 | + } |
| 45 | +} |
| 46 | + |
| 47 | +// Id implements sql.IdExpression |
| 48 | +func (n *NTile) Id() sql.ColumnId { |
| 49 | + return n.id |
| 50 | +} |
| 51 | + |
| 52 | +// WithId implements sql.IdExpression |
| 53 | +func (n *NTile) WithId(id sql.ColumnId) sql.IdExpression { |
| 54 | + ret := *n |
| 55 | + ret.id = id |
| 56 | + return &ret |
| 57 | +} |
| 58 | + |
| 59 | +// Description implements sql.FunctionExpression |
| 60 | +func (n *NTile) Description() string { |
| 61 | + return "returns percentage rank value." |
| 62 | +} |
| 63 | + |
| 64 | +// Window implements sql.WindowExpression |
| 65 | +func (n *NTile) Window() *sql.WindowDefinition { |
| 66 | + return n.window |
| 67 | +} |
| 68 | + |
| 69 | +func (n *NTile) Resolved() bool { |
| 70 | + return windowResolved(n.window) |
| 71 | +} |
| 72 | + |
| 73 | +func (n *NTile) String() string { |
| 74 | + sb := strings.Builder{} |
| 75 | + sb.WriteString("ntile()") |
| 76 | + if n.window != nil { |
| 77 | + sb.WriteString(" ") |
| 78 | + sb.WriteString(n.window.String()) |
| 79 | + } |
| 80 | + return sb.String() |
| 81 | +} |
| 82 | + |
| 83 | +func (n *NTile) DebugString() string { |
| 84 | + sb := strings.Builder{} |
| 85 | + sb.WriteString("ntile()") |
| 86 | + if n.window != nil { |
| 87 | + sb.WriteString(" ") |
| 88 | + sb.WriteString(sql.DebugString(n.window)) |
| 89 | + } |
| 90 | + return sb.String() |
| 91 | +} |
| 92 | + |
| 93 | +// FunctionName implements sql.FunctionExpression |
| 94 | +func (n *NTile) FunctionName() string { |
| 95 | + return "NTILE" |
| 96 | +} |
| 97 | + |
| 98 | +// Type implements sql.Expression |
| 99 | +func (n *NTile) Type() sql.Type { |
| 100 | + return types.Float64 |
| 101 | +} |
| 102 | + |
| 103 | +// CollationCoercibility implements the interface sql.CollationCoercible. |
| 104 | +func (*NTile) CollationCoercibility(ctx *sql.Context) (collation sql.CollationID, coercibility byte) { |
| 105 | + return sql.Collation_binary, 5 |
| 106 | +} |
| 107 | + |
| 108 | +// IsNullable implements sql.Expression |
| 109 | +func (n *NTile) IsNullable() bool { |
| 110 | + return false |
| 111 | +} |
| 112 | + |
| 113 | +// Eval implements sql.Expression |
| 114 | +func (n *NTile) Eval(ctx *sql.Context, row sql.Row) (interface{}, error) { |
| 115 | + return nil, sql.ErrWindowUnsupported.New(n.FunctionName()) |
| 116 | +} |
| 117 | + |
| 118 | +// Children implements sql.Expression |
| 119 | +func (n *NTile) Children() []sql.Expression { |
| 120 | + return n.window.ToExpressions() |
| 121 | +} |
| 122 | + |
| 123 | +// WithChildren implements sql.Expression |
| 124 | +func (n *NTile) WithChildren(children ...sql.Expression) (sql.Expression, error) { |
| 125 | + window, err := n.window.FromExpressions(children) |
| 126 | + if err != nil { |
| 127 | + return nil, err |
| 128 | + } |
| 129 | + |
| 130 | + return n.WithWindow(window), nil |
| 131 | +} |
| 132 | + |
| 133 | +// WithWindow implements sql.WindowAggregation |
| 134 | +func (n *NTile) WithWindow(window *sql.WindowDefinition) sql.WindowAdaptableExpression { |
| 135 | + nr := *n |
| 136 | + nr.window = window |
| 137 | + return &nr |
| 138 | +} |
| 139 | + |
| 140 | +func (n *NTile) NewWindowFunction() (sql.WindowFunction, error) { |
| 141 | + return aggregation.NewNTile(n.bucketExpr), nil |
| 142 | +} |
0 commit comments