sql_select
Runs an SQL select query against a database and returns the result as an array of objects, one for each row returned, containing a key for each column queried and its value.
Introduced in version 3.59.0.
If the query fails to execute, the message remains unchanged and the error can be caught using error handling methods.
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Common
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Advanced
processor:
label: ""
sql_select:
driver: "" # No default (required)
dsn: "" # No default (required)
table: "" # No default (required)
columns: [] # No default (required)
where: "" # No default (optional)
args_mapping: "" # No default (optional)processor:
label: ""
sql_select:
driver: "" # No default (required)
dsn: "" # No default (required)
table: "" # No default (required)
columns: [] # No default (required)
where: "" # No default (optional)
args_mapping: "" # No default (optional)
prefix: "" # No default (optional)
suffix: "" # No default (optional)
init_files: [] # No default (optional)
init_statement: "" # No default (optional)
conn_max_idle_time: "" # No default (optional)
conn_max_life_time: "" # No default (optional)
conn_max_idle: 2
conn_max_open: 0 # No default (optional)If the query fails to execute then the message will remain unchanged and the error can be caught using error handling methods.
Examples
Table Query (PostgreSQL)
Here we query a database for columns of footable that share a user_id
with the message user.id. A branch processor
is used in order to insert the resulting array into the original message at the
path foo_rows:
pipeline:
processors:
- branch:
processors:
- sql_select:
driver: postgres
dsn: postgres://foouser:foopass@localhost:5432/testdb?sslmode=disable
table: footable
columns: [ '*' ]
where: user_id = ?
args_mapping: '[ this.user.id ]'
result_map: 'root.foo_rows = this'Fields
args_mapping
An optional Bloblang mapping that evaluates to an array of values, one for each placeholder in the where field, in order. The values are passed to the driver as query arguments.
Type: string
# Examples:
args_mapping: root = [ this.cat.meow, this.doc.woofs[0] ]
# ---
args_mapping: root = [ meta("user.id") ]columns[]
A list of columns to query.
Type: array<string>
# Examples:
columns:
- "*"
# ---
columns:
- foo
- bar
- bazconn_max_idle
An optional maximum number of connections in the idle connection pool. If conn_max_open is greater than 0 but less than the new conn_max_idle, then the new conn_max_idle will be reduced to match the conn_max_open limit. If value ⇐ 0, no idle connections are retained. The default max idle connections is currently 2. This may change in a future release.
Type: int
Default: 2
conn_max_idle_time
An optional maximum amount of time a connection may be idle. Expired connections may be closed lazily before reuse. If value ⇐ 0, connections are not closed due to a connections idle time.
Type: string
conn_max_life_time
An optional maximum amount of time a connection may be reused. Expired connections may be closed lazily before reuse. If value ⇐ 0, connections are not closed due to a connections age.
Type: string
conn_max_open
An optional maximum number of open connections to the database. If conn_max_idle is greater than 0 and the new conn_max_open is less than conn_max_idle, then conn_max_idle will be reduced to match the new conn_max_open limit. If value ⇐ 0, then there is no limit on the number of open connections. The default is 0 (unlimited).
Type: int
driver
A database driver to use.
Type: string
Options: mysql, postgres, pgx, clickhouse, mssql, sqlite, oracle, snowflake, trino, gocosmos, spanner, databricks
dsn
A Data Source Name to identify the target database.
Drivers
The following table lists the supported drivers and their DSN formats:
| Driver | Data Source Name Format |
|---|---|
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projects/[PROJECT]/instances/[INSTANCE]/databases/[DATABASE] |
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Please note that the postgres and pgx drivers enforce SSL by default, you can override this with the parameter sslmode=disable if required.
The pgx driver is an alternative to the standard postgres (pq) driver and comes with extra functionality such as support for array insertion.
The snowflake driver supports multiple DSN formats. Please consult the docs for more details. For key pair authentication, the DSN has the following format: <snowflake_user>@<snowflake_account>/<db_name>/<schema_name>?warehouse=<warehouse>&role=<role>&authenticator=snowflake_jwt&privateKey=<base64_url_encoded_private_key>, where the value for the privateKey parameter can be constructed from an unencrypted RSA private key file rsa_key.p8 using openssl enc -d -base64 -in rsa_key.p8 | basenc --base64url -w0 (you can use gbasenc instead of basenc on OSX if you install coreutils via Homebrew). If you have a password-encrypted private key, you can decrypt it using openssl pkcs8 -in rsa_key_encrypted.p8 -out rsa_key.p8. Also, make sure fields such as the username are URL-encoded.
The gocosmos driver is still experimental, but it has support for hierarchical partition keys as well as cross-partition queries. Please refer to the SQL notes for details.
Type: string
# Examples:
dsn: clickhouse://username:password@host1:9000,host2:9000/database?dial_timeout=200ms&max_execution_time=60
# ---
dsn: foouser:foopassword@tcp(localhost:3306)/foodb
# ---
dsn: postgres://foouser:foopass@localhost:5432/foodb?sslmode=disable
# ---
dsn: oracle://foouser:foopass@localhost:1521/service_name
# ---
dsn: token:dapi1234567890ab@dbc-a1b2345c-d6e7.cloud.databricks.com:443/sql/1.0/warehouses/abc123def456init_files[]
An optional list of file paths containing SQL statements to execute immediately upon the first connection to the target database. This is a useful way to initialise tables before processing data. Glob patterns are supported, including super globs (double star).
Care should be taken to ensure that the statements are idempotent, and therefore would not cause issues when run multiple times after service restarts. If both init_statement and init_files are specified the init_statement is executed after the init_files.
If a statement fails for any reason a warning log will be emitted but the operation of this component will not be stopped.
Requires version 4.10.0 or later.
Type: array<string>
# Examples:
init_files:
- ./init/*.sql
# ---
init_files:
- ./foo.sql
- ./bar.sqlinit_statement
An optional SQL statement to execute immediately upon the first connection to the target database. This is a useful way to initialise tables before processing data. Care should be taken to ensure that the statement is idempotent, and therefore would not cause issues when run multiple times after service restarts.
If both init_statement and init_files are specified the init_statement is executed after the init_files.
If the statement fails for any reason a warning log will be emitted but the operation of this component will not be stopped.
Requires version 4.10.0 or later.
Type: string
# Examples:
init_statement: |
CREATE TABLE IF NOT EXISTS some_table (
foo varchar(50) not null,
bar integer,
baz varchar(50),
primary key (foo)
) WITHOUT ROWID;suffix
Optional SQL text to append after the generated SELECT statement, such as an ORDER BY, LIMIT, or locking clause.
Type: string
where
An optional where clause to add. Placeholder arguments are populated with the args_mapping field. Always use question marks for placeholders. They are converted to dollar syntax ($1) when the postgres, pgx, or clickhouse driver is used, and to colon syntax (:1) when the oracle or gocosmos driver is used.
Type: string
# Examples:
where: meow = ? and woof = ?
# ---
where: user_id = ?