Files
dolthub--doltgresql/server/functions/array_to_string.go
T
2026-07-13 12:32:25 +08:00

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3.1 KiB
Go

// Copyright 2024 Dolthub, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package functions
import (
"strings"
"github.com/cockroachdb/errors"
"github.com/dolthub/go-mysql-server/sql"
"github.com/dolthub/doltgresql/server/functions/framework"
pgtypes "github.com/dolthub/doltgresql/server/types"
)
// initArrayToString registers the functions to the catalog.
func initArrayToString() {
framework.RegisterFunction(array_to_string_anyarray_text)
framework.RegisterFunction(array_to_string_anyarray_text_text)
}
// array_to_string_anyarray_text represents the PostgreSQL array function taking 2 parameters.
var array_to_string_anyarray_text = framework.Function2{
Name: "array_to_string",
Return: pgtypes.Text,
Parameters: [2]*pgtypes.DoltgresType{pgtypes.AnyArray, pgtypes.Text},
IsNonDeterministic: true,
Strict: true,
Callable: func(ctx *sql.Context, paramsAndReturn [3]*pgtypes.DoltgresType, val1, val2 any) (any, error) {
arr := val1.([]any)
delimiter := val2.(string)
return getStringArrFromAnyArray(ctx, paramsAndReturn[0], arr, delimiter, nil)
},
}
// array_to_string_anyarray_text_text represents the PostgreSQL array function taking 3 parameter.
var array_to_string_anyarray_text_text = framework.Function3{
Name: "array_to_string",
Return: pgtypes.Text,
Parameters: [3]*pgtypes.DoltgresType{pgtypes.AnyArray, pgtypes.Text, pgtypes.Text},
IsNonDeterministic: true,
Strict: false,
Callable: func(ctx *sql.Context, paramsAndReturn [4]*pgtypes.DoltgresType, val1, val2, val3 any) (any, error) {
if val1 == nil {
return nil, errors.Errorf("could not determine polymorphic type because input has type unknown")
} else if val2 == nil {
return nil, nil
}
arr := val1.([]any)
delimiter := val2.(string)
return getStringArrFromAnyArray(ctx, paramsAndReturn[0], arr, delimiter, val3)
},
}
// getStringArrFromAnyArray takes inputs of any array, delimiter and null entry replacement. It uses the IoOutput() of the
// base type of the AnyArray type to get string representation of array elements.
func getStringArrFromAnyArray(ctx *sql.Context, arrType *pgtypes.DoltgresType, arr []any, delimiter string, nullEntry any) (string, error) {
baseType := arrType.ArrayBaseType()
strs := make([]string, 0)
for _, el := range arr {
if el != nil {
v, err := baseType.IoOutput(ctx, el)
if err != nil {
return "", err
}
strs = append(strs, v)
} else if nullEntry != nil {
strs = append(strs, nullEntry.(string))
}
}
return strings.Join(strs, delimiter), nil
}