-
Notifications
You must be signed in to change notification settings - Fork 26
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
docs: add sample for all data types (#51)
* docs: add sample for all data types * deps: update Spanner client to latest * docs: update comments and fix formatting * fix: use sql.NullTime + released Spanner version
- Loading branch information
Showing
7 changed files
with
305 additions
and
42 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,217 @@ | ||
| // Copyright 2021 Google LLC All Rights Reserved. | ||
| // | ||
| // 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 main | ||
|
|
||
| import ( | ||
| "context" | ||
| "database/sql" | ||
| "fmt" | ||
| "math/big" | ||
| "os" | ||
| "time" | ||
|
|
||
| "cloud.google.com/go/civil" | ||
| "cloud.google.com/go/spanner" | ||
| _ "github.com/cloudspannerecosystem/go-sql-spanner" | ||
| "github.com/cloudspannerecosystem/go-sql-spanner/examples" | ||
| ) | ||
|
|
||
| var createTableStatement = `CREATE TABLE AllTypes ( | ||
| key INT64, | ||
| bool BOOL, | ||
| string STRING(MAX), | ||
| bytes BYTES(MAX), | ||
| int64 INT64, | ||
| float64 FLOAT64, | ||
| numeric NUMERIC, | ||
| date DATE, | ||
| timestamp TIMESTAMP, | ||
| boolArray ARRAY<BOOL>, | ||
| stringArray ARRAY<STRING(MAX)>, | ||
| bytesArray ARRAY<BYTES(MAX)>, | ||
| int64Array ARRAY<INT64>, | ||
| float64Array ARRAY<FLOAT64>, | ||
| numericArray ARRAY<NUMERIC>, | ||
| dateArray ARRAY<DATE>, | ||
| timestampArray ARRAY<TIMESTAMP>, | ||
| ) PRIMARY KEY (key)` | ||
|
|
||
| // Sample showing how to work with the different data types that are supported by Cloud Spanner: | ||
| // 1. How to get data from columns of each type. | ||
| // 2. How to set data of each type as a statement parameter. | ||
| // | ||
| // Execute the sample with the command `go run main.go` from this directory. | ||
| func dataTypes(projectId, instanceId, databaseId string) error { | ||
| ctx := context.Background() | ||
| db, err := sql.Open("spanner", fmt.Sprintf("projects/%s/instances/%s/databases/%s", projectId, instanceId, databaseId)) | ||
| if err != nil { | ||
| return fmt.Errorf("failed to open database connection: %v\n", err) | ||
| } | ||
| defer db.Close() | ||
|
|
||
| // Statement parameters can be given as either native types (string, bool, int64, ...) or as nullable struct types | ||
| // defined in the Spanner client library (spanner.NullString, spanner.NullBool, spanner.NullInt64, ...). | ||
|
|
||
| // Insert a test row with all non-null values using DML and native types. | ||
| if _, err := db.ExecContext(ctx, `INSERT INTO AllTypes ( | ||
| key, bool, string, bytes, int64, float64, numeric, date, timestamp, | ||
| boolArray, stringArray, bytesArray, int64Array, float64Array, numericArray, dateArray, timestampArray) | ||
| VALUES (@key, @bool, @string, @bytes, @int64, @float64, @numeric, @date, @timestamp, | ||
| @boolArray, @stringArray, @bytesArray, @int64Array, @float64Array, @numericArray, @dateArray, @timestampArray)`, | ||
| 1, true, "string", []byte("bytes"), 100, 3.14, *big.NewRat(1, 1), civil.DateOf(time.Now()), time.Now(), | ||
| []bool{true, false}, []string{"s1", "s2"}, [][]byte{[]byte("b1"), []byte("b2")}, []int64{1, 2}, | ||
| []float64{1.1, 2.2}, []big.Rat{*big.NewRat(1, 2), *big.NewRat(1, 3)}, | ||
| []civil.Date{{2021, 10, 12}, {2021, 10, 13}}, | ||
| []time.Time{time.Now(), time.Now().Add(24 * time.Hour)}); err != nil { | ||
| return fmt.Errorf("failed to insert a record with all non-null values using DML: %v", err) | ||
| } | ||
| fmt.Print("Inserted a test record with all non-null values\n") | ||
|
|
||
| // Insert a test row with all null values using DML and Spanner Null* types. | ||
| if _, err := db.ExecContext(ctx, `INSERT INTO AllTypes ( | ||
| key, bool, string, bytes, int64, float64, numeric, date, timestamp, | ||
| boolArray, stringArray, bytesArray, int64Array, float64Array, numericArray, dateArray, timestampArray) | ||
| VALUES (@key, @bool, @string, @bytes, @int64, @float64, @numeric, @date, @timestamp, | ||
| @boolArray, @stringArray, @bytesArray, @int64Array, @float64Array, @numericArray, @dateArray, @timestampArray)`, | ||
| 2, spanner.NullBool{}, spanner.NullString{}, []byte(nil), // There is no NullBytes type | ||
| spanner.NullInt64{}, spanner.NullFloat64{}, spanner.NullNumeric{}, spanner.NullDate{}, spanner.NullTime{}, | ||
| // These array values all contain two NULL values in the (non-null) array. | ||
| []spanner.NullBool{{}, {}}, []spanner.NullString{{}, {}}, [][]byte{[]byte(nil), []byte(nil)}, | ||
| []spanner.NullInt64{{}, {}}, []spanner.NullFloat64{{}, {}}, []spanner.NullNumeric{{}, {}}, | ||
| []spanner.NullDate{{}, {}}, []spanner.NullTime{{}, {}}); err != nil { | ||
| return fmt.Errorf("failed to insert a record with all null values using DML: %v", err) | ||
| } | ||
| fmt.Print("Inserted a test record with all typed null values\n") | ||
|
|
||
| // The Go sql driver supports inserting untyped nil values for NULL values. Cloud Spanner also supports untyped NULL | ||
| // values. The Spanner emulator however does not (yet) support this, which is why this part of the code sample is | ||
| // currently disabled on the emulator. Running it against a real Cloud Spanner database works. | ||
| if os.Getenv("SPANNER_EMULATOR_HOST") == "" { | ||
| if _, err := db.ExecContext(ctx, `INSERT INTO AllTypes ( | ||
| key, bool, string, bytes, int64, float64, numeric, date, timestamp, | ||
| boolArray, stringArray, bytesArray, int64Array, float64Array, numericArray, dateArray, timestampArray) | ||
| VALUES (@key, @bool, @string, @bytes, @int64, @float64, @numeric, @date, @timestamp, | ||
| @boolArray, @stringArray, @bytesArray, @int64Array, @float64Array, @numericArray, @dateArray, @timestampArray)`, | ||
| 3, nil, nil, nil, nil, nil, nil, nil, nil, | ||
| nil, nil, nil, nil, nil, nil, nil, nil); err != nil { | ||
| return fmt.Errorf("failed to insert a record with all untyped null values using DML: %v", err) | ||
| } | ||
| fmt.Print("Inserted a test record with all untyped null values\n") | ||
| } | ||
|
|
||
| // You can use the same types for getting data from a column as for setting the data in a statement parameter, | ||
| // except for ARRAY columns. Arrays must be stored in a []spanner.Null* variable, as all arrays may always | ||
| // contain NULL elements in the array. | ||
| var r1 nativeTypes | ||
| if err := db.QueryRowContext(ctx, "SELECT * FROM AllTypes WHERE key=@key", 1).Scan( | ||
| &r1.key, &r1.bool, &r1.string, &r1.bytes, &r1.int64, &r1.float64, &r1.numeric, &r1.date, &r1.timestamp, | ||
| &r1.boolArray, &r1.stringArray, &r1.bytesArray, &r1.int64Array, &r1.float64Array, &r1.numericArray, &r1.dateArray, &r1.timestampArray, | ||
| ); err != nil { | ||
| return fmt.Errorf("failed to get row with non-null values: %v", err) | ||
| } | ||
| fmt.Print("Queried a test record with all non-null values\n") | ||
|
|
||
| // You can also use the spanner.Null* types to get data. These types can store both non-null and null values. | ||
| var r2 nullTypes | ||
| if err := db.QueryRowContext(ctx, "SELECT * FROM AllTypes WHERE key=@key", 1).Scan( | ||
| &r2.key, &r2.bool, &r2.string, &r2.bytes, &r2.int64, &r2.float64, &r2.numeric, &r2.date, &r2.timestamp, | ||
| &r2.boolArray, &r2.stringArray, &r2.bytesArray, &r2.int64Array, &r2.float64Array, &r2.numericArray, &r2.dateArray, &r2.timestampArray, | ||
| ); err != nil { | ||
| return fmt.Errorf("failed to get row with null values: %v", err) | ||
| } | ||
| fmt.Print("Queried a test record with all null values and stored these in spanner.Null* variables\n") | ||
|
|
||
| // You can also use the sql.Null* types where these are available. Note that the Go sql package | ||
| // does not contain any types for nullable numeric and date values, so for these you must always | ||
| // use spanner.NullNumeric and spanner.NullDate. | ||
| var r3 sqlNullTypes | ||
| if err := db.QueryRowContext(ctx, "SELECT * FROM AllTypes WHERE key=@key", 1).Scan( | ||
| &r3.key, &r3.bool, &r3.string, &r3.bytes, &r3.int64, &r3.float64, &r3.numeric, &r3.date, &r3.timestamp, | ||
| &r3.boolArray, &r3.stringArray, &r3.bytesArray, &r3.int64Array, &r3.float64Array, &r3.numericArray, &r3.dateArray, &r3.timestampArray, | ||
| ); err != nil { | ||
| return fmt.Errorf("failed to get row with null values using Go sql null types: %v", err) | ||
| } | ||
| fmt.Print("Queried a test record with all null values and stored these in sql.Null* variables\n") | ||
|
|
||
| return nil | ||
| } | ||
|
|
||
| type nativeTypes struct { | ||
| key int64 | ||
| bool bool | ||
| string string | ||
| bytes []byte | ||
| int64 int64 | ||
| float64 float64 | ||
| numeric big.Rat | ||
| date civil.Date | ||
| timestamp time.Time | ||
| // Array types must always use the Null* types, because an array may always | ||
| // contain NULL elements in the array itself (even if the ARRAY column is | ||
| // defined as NOT NULL). | ||
| boolArray []spanner.NullBool | ||
| stringArray []spanner.NullString | ||
| bytesArray [][]byte | ||
| int64Array []spanner.NullInt64 | ||
| float64Array []spanner.NullFloat64 | ||
| numericArray []spanner.NullNumeric | ||
| dateArray []spanner.NullDate | ||
| timestampArray []spanner.NullTime | ||
| } | ||
|
|
||
| type nullTypes struct { | ||
| key int64 | ||
| bool spanner.NullBool | ||
| string spanner.NullString | ||
| bytes []byte // There is no spanner.NullBytes type | ||
| int64 spanner.NullInt64 | ||
| float64 spanner.NullFloat64 | ||
| numeric spanner.NullNumeric | ||
| date spanner.NullDate | ||
| timestamp spanner.NullTime | ||
| boolArray []spanner.NullBool | ||
| stringArray []spanner.NullString | ||
| bytesArray [][]byte | ||
| int64Array []spanner.NullInt64 | ||
| float64Array []spanner.NullFloat64 | ||
| numericArray []spanner.NullNumeric | ||
| dateArray []spanner.NullDate | ||
| timestampArray []spanner.NullTime | ||
| } | ||
|
|
||
| type sqlNullTypes struct { | ||
| key int64 | ||
| bool sql.NullBool | ||
| string sql.NullString | ||
| bytes []byte // There is no sql.NullBytes type | ||
| int64 sql.NullInt64 | ||
| float64 sql.NullFloat64 | ||
| numeric spanner.NullNumeric // There is no sql.NullNumeric type | ||
| date spanner.NullDate // There is no sql.NullDate type | ||
| timestamp sql.NullTime | ||
| // Array types must always use the spanner.Null* structs. | ||
| boolArray []spanner.NullBool | ||
| stringArray []spanner.NullString | ||
| bytesArray [][]byte | ||
| int64Array []spanner.NullInt64 | ||
| float64Array []spanner.NullFloat64 | ||
| numericArray []spanner.NullNumeric | ||
| dateArray []spanner.NullDate | ||
| timestampArray []spanner.NullTime | ||
| } | ||
|
|
||
| func main() { | ||
| examples.RunSampleOnEmulator(dataTypes, createTableStatement) | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.