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IDENTIFIER clause

Applies to: check marked yes Databricks SQL check marked yes Databricks Runtime 13.3 LTS and above

The IDENTIFIER clause enables SQL-injection-safe parameterization of identifiers in SQL statements.

  • Applies to: check marked yes Databricks Runtime 18.0 and above

    The clause can be used instead of any object name or identifier within a multipart name, as long as the arguments consist only of a string literal or string parameter marker. This includes coalesced strings such as: 'myschema' :table 'mycolumn' or :schema :table :column.

  • Applies to: check marked yes Databricks SQL check marked yes Databricks Runtime 13.3 LTS and above

    The IDENTIFIER clause interprets a constant string such as 'myschema' || :table || 'mycolumn' or :schema || :table || :column as a:

    • relation (table or view) name
    • function name
    • column name
    • field name
    • schema name
    • catalog name

    The IDENTIFIER clause is limited to the following statements:

    • The table, view, or function subject name of a CREATE, ALTER, DROP, or UNDROP statement.
    • The target table name of a MERGE, UPDATE, DELETE, INSERT, COPY INTO statements.
    • The target of a SHOW or DESCRIBE statement.
    • USE of a schema or catalog
    • A function invocation
    • A column, table or view referenced in a query. This includes queries embedded in a DDL or DML statement.

Note

Where the IDENTIFIER clause is not supported and SQL injection is not a concern, you can use EXECUTE IMMEDIATE instead. For example: EXECUTE IMMEDIATE 'CREATE TABLE ' || :tab || '(' || :col || 'INT)';

Syntax

IDENTIFIER ( strLiteral )

IDENTIFIER ( strExpr )

Parameters

  • strLiteral: A STRING literal typically composed of one or more string parameter markers and literal components which are coalesced;
  • strExpr: A constant STRING expression typically including one or more parameter markers. Starting with Databricks Runtime 18.0 this notation is deprecated.

Examples

Scala

// Creation of a table using parameter marker.
spark.sql("CREATE TABLE IDENTIFIER(:mytab)(c1 INT)", args = Map("mytab" -> "tab1"))

// Altering a table with a fixed schema and a parameterized table name.
spark.sql("ALTER TABLE IDENTIFIER('default.' || :mytab) ADD COLUMN c2 INT)", args = Map("mytab" -> "tab1"))

// Altering a table with a fixed schema and a parameterized table name in DBR 18.0 and above.
spark.sql("ALTER TABLE IDENTIFIER('default.' :mytab) ADD COLUMN c2 INT)", args = Map("mytab" -> "tab1"))

// Dropping a table with separate schema and table parameters.
spark.sql("DROP TABLE IDENTIFIER(:myschema || '.' || :mytab)", args = Map("mySchema" -> "default", "mytab" -> "tab1"))

// Dropping a table with separate schema and table parameters in DBR 18.0 and above.
spark.sql("DROP TABLE IDENTIFIER(:myschema '.' :mytab)", args = Map("mySchema" -> "default", "mytab" -> "tab1"))

// A parameterized reference to a table in a query. The table name is qualified and uses back-ticks.
spark.sql("SELECT * FROM IDENTIFIER(:mytab)", args = Map("mytab" -> "`default`.`tab1`"))

// You cannot qualify the IDENTIFIER claue or use it as a qualifier itself.
spark.sql("SELECT * FROM myschema.IDENTIFIER(:mytab)", args = Map("mytab" -> "`tab1`"))

spark.sql("SELECT * FROM IDENTIFIER(:myschema).mytab", args = Map("mychema" -> "`default`"))

// A parameterized column reference
spark.sql("SELECT IDENTIFIER(:col) FROM VALUES(1) AS T(c1)", args = Map("col" -> "t.c1"))

// Passing in an aggregate function name as a parameter
spark.sql("SELECT IDENTIFIER(:agg)(c1) FROM VALUES(1), (2) AS T(c1)", args = Map("agg" -> "max"))

SQL


-- Using a catalog using a variable.
> DECLARE mycat = 'main';
> USE CATALOG IDENTIFIER(mycat);

-- Creation of a table using variable.
> DECLARE mytab = 'tab1';
> CREATE TABLE IDENTIFIER(mytab)(c1 INT);

-- Altering a table with a fixed schema and a parameterized table name.
> ALTER TABLE IDENTIFIER('default.' || mytab) ADD COLUMN c2 INT;

-- Altering a table with a fixed schema and a parameterized table name in DBR 18.0 and above.
> ALTER TABLE IDENTIFIER('default.' || mytab) ADD COLUMN c2 INT;

-- Inserting using a parameterized table name. The table name is qualified and uses back-ticks.
> SET VAR mytab = '`default`.`tab1`';
> INSERT INTO IDENTIFIER(mytab) VALUES(1, 2);

-- A parameterized reference to a table in a query.
> SELECT * FROM IDENTIFIER(mytab);
  1   2

-- Dropping a table with separate schema and table parameters.
> DECLARE myschema = 'default';
> SET VAR mytab = 'tab1';
> DROP TABLE IDENTIFIER(myschema || '.' || mytab);
-- In DBR 18.0 and above:
> DROP TABLE IDENTIFIER(myschema '.' mytab);

-- You cannot qualify the IDENTIFIER clause or use it as a qualifier itself prior to DBR 18.0.
> SELECT * FROM myschema.IDENTIFIER('tab');
Error: PARSE_SYNTAX_ERROR

> SELECT * FROM IDENTIFIER('default').mytab;
Error: PARSE_SYNTAX_ERROR

-- A parameterized column reference
> DECLARE col = 't.c1';
> SELECT IDENTIFIER(col) FROM VALUES(1) AS T(c1);
  1

-- Passing in an aggregate function name as a parameter
> DECLARE agg = 'max';
> SELECT IDENTIFIER(agg)(c1) FROM VALUES(1), (2) AS T(c1);
  2
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