Sqlglot column level lineage example. Arguments: column: The column to build the lineage for. 110 Additionally, we can't remove predicates from their original form. """ 178 if isinstance Datafold's Column-Level Lineage—which yes, leverages sqlglot, because it's awesome—connects your entire data warehouse (not only dbt models) to downstream BI tools: Looker, Tableau, and others Oct 25, 2021 · 2. It aims to read a wide variety of SQL inputs and output syntactically and semantically correct SQL in the targeted dialects. Since then, there’s been quite a bit of development and refinement of this feature in almost every following release, the latest in v0. It aims to read a wide variety of SQL inputs and output syntatically correct SQL in the targeted dialects. Feature description. Managed DataHub. tb2 col8. Jan 10, 2024 · Column-Level Lineage is the backbone of sophisticated data governance protocols, offering detailed traceability and transparency. Details displays column-level lineage for models open in the editor and results of queries. In these cases, lineage may be incomplete and dbt Cloud will provide a warning about it in the column lineage. For example, changing the order of boolean expressions chained by the AND operator can also be treated as non-breaking. In Cluster, select a cluster with access to Unity Catalog. lineage import lineage # pip show sqlglot # Name: sqlglot # Version: 18. Behind the scene, SQLLineage pluggable leverages parser library ( sqlfluff and sqlparse) to parse the SQL command, analyze the AST, stores the May 10, 2023 · For example, the query I provided at the beginning of this section can have the following AST representation: Figure 1: Abstract Syntax Tree derived from a SQL query. quote_identifiers: Whether to run the quote_identifiers step. sources: A mapping of queries which will be used to continue building lineage. sql: The SQL string or expression. May 5, 2024 · Lineage Visualization. Best Open Source Data Lineage Tools — 1. 3 (continuedfrompreviouspage) IntermediateTables: db1. I've tried to solve this problem using some python library: 1) Even extracting only tables using sqlparse might be a huge problem. foo. Just click on a table’s schema and select the column whose impact you want to analyze. You'll now be in a new tab with the current Node highlighted in blue. 2. Example DAG. Prerequisites For this tutorial, you need to deploy DataHub Quickstart and ingest sample data. You can find a complete source code in the diff. At a high level, a data lineage system typically provides data teams and consumers with one or both of the following resources: A visual graph (DAG) of sequential workflows at the data set or column level. Text and Transpiling But column level lineage was developed by the community and for the community. Oct 1, 2022 · Excluding columns that come from calculated columns and given that I have the schema structure for all tables and columns. For example: Lets say I want to find the source table for the 'COL1' at the final select. SQLMesh is a next-generation data transformation and modeling framework that is backwards compatible with dbt. Selecting View Column Lineage. 27. Resolve challenging data issues with root cause analysis. Column): 168 if column. <default>. MODEL because that's the source (sources argument to the lineage function) where that column appears. Column-level lineage systems can be implemented using a variety of technologies, such as data catalogs, data lakes, and data warehouses. (Note: details pane is collapsed by default. I like the "model header" thing more than dbt's "half in sql, half in yaml" approach, but that is kind of cosmetic. Statements (#): 1. expressions as exp. With the v2 plugin, lineage extraction has been enhanced by leveraging Airflow's OpenLineage extractors and DataHub's robust SQL parser. Install; Versioning; Get in Touch; Examples. Step 1. Enhancement smarter column-to-table resolution using query context . db in unnest_aliases: 171 column. DataHub started supporting basic column-level lineage for limited sources from v0. failed to parse source table from subquery with more than one parenthesis . 5 and Trino; column-level lineage is needed (Iceberg table format is used)! We know about The parser. what's after the IN part) and and some others ("implicit columns") that exist in the schema of the pivoted table but don't appear in the AST of the PIVOT operator. Take this SQL for example: d. Tokern. Impact Analysis at the column level. It allows you to track the inputs from which a data asset is derived, along with the data assets that depend on it downstream. With robust column-level lineage in place, data professionals can accurately categorize and classify their data. Enter a name for the notebook and select SQL in Default Language. In this article, I’ll teach you how you can rapidly debug your pipelines without using column-level lineage. SCHEMA. x xx , 'SOMETHING' yy, from polls p ; """ aliases = [i. SQLGlot parses SQL into an abstract syntax tree (AST). Behind the scene, SQLLineage pluggable leverages parser library sqlfluff and sqlparse to parse the SQL command, analyze the AST, stores the lineage information in a graph (using Column level lineage is freely available for dbt users through SQLMesh's open-source UI. It moves beyond a broad overview with table-level lineage (TLL) to detailed insights with column-level lineage (CLL), revealing transformations at the column level. Expression)-> exp. I tried to find it via going thru the scope but couldnt managed to do it. e. Behind the scene, SQLLineage pluggable leverages parser library sqlfluff and sqlparse to parse the SQL command, analyze the AST, stores the lineage information in a graph (using Oct 19, 2023 · Column-level lineage is a multi-purpose tool that data engineers and data owners can use to: Increase overall data quality. Name: sqlglot Version: 22. ). I was thinking of approaching this by parsing the SQL that generated or inserted data into each table (this might include nested queries, auxiliary tables, etc. Additionally, we’re looking into using the column-level lineage in SQLMesh to About DataHub Lineage. scope: A pre-created scope to use instead. Data Teams often have the following problem: Column level lineage is not working as expected when not providing alias or table name before column name. . MetaData-Awareness Lineage By observing the column lineage generated from previous step, you’ll possibly notice that: <default>. -generated images made using OpenAI’s DALL-E 3. SQLGlot was our pick to zoom into the column usage in our Oracle DB. table in unnest_aliases: 169 column. In the future, additional heuristics will be added to the algorithm to automatically detect other kinds of non-breaking changes. One more cool feature, if you want a graph visualization for the lineage result, toggle graph-visualization option. Jan 13, 2024 · The difficulty stems from the fact that when you pivot a table, you have some columns that are produced as a function of the value list (i. So hiding such a beloved and easy feature to implement (once you have SQLGlot) behind a paywall is unfortunate. It supports better understanding and management of data origins, destinations, and transformations. It dramatically extends the reach of SQLFlow: Visualize column impact and data lineage to track columns across transformations by analyzing SQL query. supported databases: bigquery, couchbase, dax, db2 Hey there, I am currently trying to build a column lineage tool on my data model. That's how that field seems to work in other queries. sql A webserver will be started, showing DAG representation of the lineage result in browser: Table-Level Lineage; Column-Level Lineage Apr 27, 2023 · Future work. dialects. *: the wildcard is not expanded. 111 """ 112 # find all the tables that can be pushdown too 113 # these are tables that are referenced in all I would expect the MODEL_ALIAS. Wanted to give sqlglot a shoutout as it saved me a ton of time. Credit: OpenAI. From here you can select different columns of the selected node and it's lineage will be highlighted The implementation discussed in this post is now a part of the SQLGlot library. 5. My vision is to unify dlt and sqlmesh metadata to craft an end-to-end data platform. lineage: the top level key of the lineage file containing a list of EntityNodeConfig objects. Errors can occur when parsing fails or a column's origin is unknown (like with JSON unpacking, lateral joins, and so on). This step is necessary to ensure correctness for case sensitive queries. Still using the above SQL file. An industry first, Metaphor now supports column level lineage for PowerBI Datasets. It simplified our process and made it more efficient. Below is a partial view of the AST generated for the customers model. SQLGlot powers column level lineage for yet another product. The first step is to take the raw SQL and parse out an AST. column_mapping: a column mapping that describes the structure of the table. validate_qualify_columns: Whether to validate columns. problem with SELECT CAST(CASE WHEN …END AS DECIMAL(M,N)) AS col_name . Level Up Coding. Click Create. rc. quux. Currently, the only version released is 1. It is currently the fastest pure-Python SQL parser. Testing Data quality checks such as detecting NULL values and duplicated rows are extremely valuable for detecting upstream data issues and large scale problems. parse_one(s). v1. dbt Labs announced the feature… Given sqlmesh's underlying sqlglot, column-level lineage is at my fingertips. Add column-level lineage between datasets. game_platform_id I'm trying to generate column level lineage from given INSERT statement. Seems quite convoluted. schema: The schema of tables. The first step is to convert the sql string into a list of tokens. I expect to get same expression of last step in walk for sql_nok as in sql_ok. tb2 col2. The best way to glean the structure of a particular AST is python's builtin repr function: repr ( ast ) For more information about data lineage, refer to About DataHub Lineage. Use Cases . Without deep visibility into column level lineage it's near impossible to find why a report doesn’t show the information you were expecting to see. * <- <default>. DataHub Controls that let you view just what you need. Let’s walk through the whole parsing pipeline using the same customers model above. com Jan 25, 2024 · The one billion row challenge is exploding in popularity. Dec 3, 2023 · A. After installation, you will get a sqllineage command. 8. dialect: The dialect of input SQL. Contributions are very greet in SQLGlot; read the contribution guide up get began! Table of Contents. Automate large-scale changes in hours. You can use my library SQLGlot to parse your SQL and extract out the information. Given a SQL command, SQLLineage will tell you its source and target tables, without worrying about Tokens, Keyword, Identified and all the jagons used by a SQL parser. A data catalog 1 from __future__ import annotations 2 3 import itertools 4 import typing as t 5 6 from sqlglot import alias, exp 7 from sqlglot. It can be used to format SQL or translate between different dialects like Presto, Spark, and Hive. Currently the lineage is at the table level which means that if you need to change or monitor a specific column or a set of columns, you should manually search in the relevant tables how each column is transformed and what its current status in each step or table in your data flow. Aug 29, 2023 · SQL parsing is the process of deconstructing a SQL query to extract different information like fields, tables, filters, joins etc. Here is my problem: given a SQL query, e. One could also define this model by simply returning a string that contained the SQL query of the SQL-based example. But this is only the first step in a broader, ongoing project to implement the feature across the project, and we’d love your help. SQL Diagram (Part 3): SQL-to-ERD with DDL. 1 sql = ''' with step2 as Apr 7, 2024 · table/column lineage mixed up for self dependent SQL . Right-click on any populated column and select View Column Lineage. Data lineage is vital for navigating the complex data paths within an organization. Feature Availability. It affords data users better understanding of their data, and provides clear visibility into where their data’s coming from; where it’s going; and how it’s been changed, by whom, and why. Strings used as pre/post-statements or return values in Python-based models will be parsed into SQLGlot expressions, which means that SQLMesh will still be able to understand them semantically and thus provide information such as column-level lineage. DataHub’s mission is to equip how organizations understand and utilize their data through sophisticated metadata management. A SQL parser and transpiler that supports 10+ dialects and can trans-parsing SQL between dialects. One of our most frequently requested new features, column-level lineage makes dataset column inputs and outputs available via the Marquez API. Jun 19, 2023 · With column-level lineage, you can unlock powerful insights into how your data moves to enable fine-tuned root cause and impact analysis, reactive troubleshooting, increased visibility into PII data, and more. Running the SQLGlot tokenizer shows the output. It supports lineage for databases, dashboards, and pipelines, offering both table and column-level traceability. I'm exploring column RUN_DATE, and expect to get expression for last available downstream. You may export database structure into a SQL file which includes CREATE TABLE/CREATE VIEW/ CREATE PROCEDURE and other SQL statements. Python code Jun 13, 2022 · The ability of lineage to extend transparency around sensitive items and peripheral consequences of data increases an organization’s efficacy and improves data stewardship. Yes, it's built on top of SQLGlot :) Here's a step by step guide showing how you can spin up column level Column level lineage is freely available for dbt users through SQLMesh's open-source UI. Column-level lineage is useful in a variety of industries and for a variety of reasons. Column level lineage is freely available for dbt users through SQLMesh's open-source UI. 2 days ago · Column-level lineage relies on SQL parsing. SQLGlot's tokenizer is quite simple and can be found here. In short, it enables better data governance by giving you a more I really like the idea of "like dbt but it actually understands the code" - column lineage based automated impact analysis is awesome. Feb 15, 2024 · Related issues Everything was fixed in backward compatible way, should not break anything #9841 #9842 #9843 #9844 #9845 #9846 #9847 Features force_extraction_of Nov 20, 2023 · For example, a financial institution might plan to update its customer data model. dialect import DialectType 8 from sqlglot. Here is a snippet of code that should help you get started. I had a task that involved building a dependency graph by statically analyzing the relationship of MySQL views. 3 Date: December 26, 2021. Assess the scope of proposed changes with impact analysis. col8; The result should looks this way: tb1 col1. And it is hand-written parser. With column-level lineage, the institution can predict how these updates will affect its risk assessment Column level lineage is not working as expected when not providing alias or table name before column name. It specifies the data types for all columns in the file: the holiday_name column is data type VARCHAR and the holiday_date column is data type DATE. The SQL is a monstrous language. tb1 col7. SELECT T. Modifying the lineage parser according to our customer's requirements becomes achievable. 1 sql = ''' with step2 as I'm looking for potential solutions that would work well with many custom things but would support Spark 3. col4 <- col4: col4 is not assigned with source table. How well does Python stack up? · 10 min read · 5 days ago Mar 22, 2023 · With our own parser in place, we decided to start adapting it to support column-level lineage. set ("table", None) 170 elif column. My current stack is Snowflake + dbt. SELECT. I've even been told by many people that it's "doing it the wrong way". Feb 26, 2024 · It was born out of LinkedIn’s attempt to solve search and discovery of data assets at scale. sqllineage,Release1. Goal Of This Guide This guide will show you how to. The answer is from the column INNER_COL1 from the table S1 May 10, 2024 · SQLGlot is a no-dependency SQL parser, transpiler, optimizer, and engine. Aug 24, 2023 · However, it should live noted that SQL validation is cannot SQLGlot’s goal, so some syntax errors mayor go unnoticed. It will automatically expand upon opening a model in the editor or running a query. sqllineage -g -f foo. 1. It’s not perfect because we don’t know the columns encoded in * of table quux. It can be used to format SQL or translate between 21 different dialects like DuckDB, Presto / Trino, Spark / Databricks, Snowflake, and BigQuery. The potential here is massive! 107 def pushdown_dnf (predicates, sources, scope_ref_count): 108 """ 109 If the predicates are in DNF form, we can only push down conditions that are in all blocks. Build the lineage graph for a column of a SQL query. table1 1. 12. Data Lineage is used to capture data dependencies within an organization. Column-level lineage is a worthy pursuit. yml file with the following top-level keys: version: the version of lineage file config the config conforms to. EntityNodeConfig: EntityConfig: name: identifier of the entity. To capture lineage data, use the following steps: Go to your Databricks landing page, click New in the sidebar, and select Notebook from the menu. 28 onwards. optimizer. Optimize data storage and compute costs. 0. We’re pleased to be able to share this new feature now, and we welcome contributors to this May 10, 2023 · Sqlglot. ) It also contains nine buttons: Toggle Editor/Docs/Errors toggles among the Code Editor (default), Docs, and Errors views. g. This allows you to trace the lineage of each row back to its source. As a open source data lineage Tool, Tokern is built for cloud data warehouses and data lakes, taking a dedicated approach which allows users to obtain column-level data lineage from databases and data Aug 29, 2023 · Here is the column-level lineage diagram, with columns represented in the ERD-style, within their parent tables: In real life, there could be way too many connections at this granularity level. py module. col7 = tb2. Feb 16, 2018 · 1. The way SQLGlot computes column level lineage is unique. scope import Scope, traverse_scope 10 from sqlglot. For example, one issue is that when you Python SQL Parser and Transpiler. The motivating problem. Query parsing is used in all the database backends primarily by The tree. col2 from tb1 as a inner join tb2 as b on tb1. May 12, 2022 · In this article, I will introduce 5 best open source data lineage tools in 2022 for you. I am completely new to using sqlglot library and I find it difficult to get going with the documentation. Add lineage between datasets. In a while loop, it checks each character and either appends the character to the current token, or makes a new token. Oct 13, 2023 · Column-level lineage enables data professionals to track the lifecycle of individual columns in a database, crucial for maintaining data accuracy, mitigating risk, and enhancing decision-making. SQLGlot’s main purpose is to parse an input SQL query written in any of the 19 (at the time of writing) supported dialects and produce a tree-like data structure like the one above. The choice of SQLglot was an obvious one due to its simple but powerful API, lack of external dependencies and, more importantly, extensive list of supported SQL dialects. Maybe somewhere in the future, we can provide some kind of plugin mechanism to register metadata as a supplement to refine the lineage result, but in no way Column Level Lineage: painkiller or vitamin? wondering why column level lineage (CLL) is a hot topic, Here&#39;s a quick recap: 1. alias for i in sqlglot. SQLLineage comes to the rescue. Arguments: table: the Table expression instance or string representing the table. 3Dialect-AwarenessLineage Bydefault May 10, 2024 · Overall, data lineage is a fundamental concept to understand in the practice of analytics engineering and modern data work. I did not found any straightforward "ready to use function" to do so, but I th sqlglot - Amazing SQL parsing library. Yes, it's built on top of SQLGlot :) Here's a step by step guide showing how you can spin up column level Sep 2, 2022 · In its current form, column-level lineage in OpenLineage is limited to the Spark integration and not yet visible in the Marquez UI. Initially, I was using sqlparse to extract the dependencies from the SQL statements, but it required me to create an increasingly qualify_columns: Whether to qualify columns. Instead of using a logical plan like most other SQL engines, SQLGlot Tokenizing. I wish it could make it a website like dbt does too. The Significance of Data Lineage. So I am trying to build a data catalog for my Snowflake database, and I want to be able to know exactly which columns generated a specific column in my tables. For example, changing the query to: DataHub's lineage feature is a critical tool for understanding data dependencies and the flow of data across an organization. schema import Schema 11 12 if t. The added table must have the necessary number of qualifiers in its path to match the schema's nesting level. A few examples include: Additionally, having a first-class understanding of SQL supercharges SQLMesh with features such as transpilation, column-level lineage, and automatic change categorization. from sqlglot import parse_one ast = parse_one ( "SELECT a FROM (SELECT a FROM x) AS x") An AST is a data structure that represents a SQL statement. $ sqllineage -e "insert into table_foo select * from table_bar union select * from table_baz". helper import csv_reader, name_sequence 9 from sqlglot. For example, this shows a seed model definition that includes the columns key. sql = """. Each child table contains a foreign key column _dlt_parent_id linking to a particular row ( _dlt_id) of a parent table. 2. One of the hot topics is, of course, column-level lineage. For example this official book doesn't work properly at all. There are so many open source options now to get column level lineage for dbt. To view Column Lineage, take the following steps: Open a node. Achieving Excellence Nov 4, 2022 · Toggle the Show Columns control to switch between table-level and column-level lineage — in one click — without switching tabs, or losing context. 3. Yes, it's built on top of SQLGlot :) Here's a step by step guide showing how you can spin up column level Aug 21, 2023 · In dlt, each row in all (top level and child) data tables created by dlt contains a unique column named _dlt_id. Oct 13, 2023 · It can theoretically be used to trace back a column-level lineage of your warehouse by analyzing SQL files. col1, b. Apr 19, 2024 · SQLGlot is a no-dependency SQL parser, transpiler, optimizer, and engine. For example, duckdb's select. DataHub is building tools and features for SQLGlot is a no dependency Python SQL parser, transpiler, and optimizer. As we journey through the evolving landscape of SQL management, I’ve found SQLGlot to be more than just a tool — it’s a The lineage source file should be a . Learn more about the SQLGlot API in the documentation. set ("db", None) 172 173 return expression 174 175 176 def unnest_to_explode (expression: exp. y [2] has 3700 lines, and this is only for SELECT. Rant: People doing "SELECT *" in production have a special place in hell 😂 Content: Let's get back to Data Lineage. Some implementing classes may require column information to also be provided. Behind the scene, SQLLineage pluggable leverages parser library sqlfluff and sqlparse to parse the SQL command, analyze the AST, stores the lineage information in a graph (using OpenMetadata provides a comprehensive solution for tracking and visualizing data lineage, which is crucial for understanding data transformations and usage within an organization. import sqlglot. Users can interact with the lineage view to explore NOTE: Specifying column names and data types is required for Python models that return DataFrames. Also this will probably break sqlfluff. ZetaSQL's grammar file [3] is almost 10k lines. Bugfix column lineage for union operation Oct 25, 2022 · We are excited to announce the addition of column-level lineage to Marquez with the release of 0. See full list on sqlglot. Then using a SQL parser to analyze those scripts to get metadata from those SQL scripts and build data lineage of the table/columns. Mar 22, 2022 · Data lineage is one of the more interesting and useful applications of metadata. This new approach worked much better. Example of warning in the full lineage graph. If SQLGlot didn’t recognize a column that we knew existed, we ran the lineage parsing again without telling it anything about the table columns. SQLGlot is a no-dependency SQL parser, transpiler, optimizer, and engine. This size is amazing if it's really capable, but I intuitively doubt it. -f option let you pass a file that contains SQL statements. A node to have source_name equal to SNOWFLAKE. Self-Hosted DataHub. Here is example: from sqlglot. It has two major options: -e option let you pass a quoted query string as SQL statements. This parser uses metadata to generate column-level lineage, offering a more schema Dec 19, 2023 · Most lineage tools also painstakingly calculate column-level lineage, which allows you to trace a metric all the way through your project. Congrats to Rex Ledesma and the Dagster Labs team for an Given a SQL command, SQLLineage will tell you its source and target tables, without worrying about Tokens, Keyword, Identified and all the jagons used by a SQL parser. But this flag is provided in case this step is performed at a later time. expressions] Output: ['xx', 'yy'] In case there are any column selections that do not have an alias, you can retain the expression itself: Feb 25, 2016 · Select a. dateCooked, Column-Level Lineage Design Key Design Principles sqllineage will stay primarily as a static code analysis tool, so we must tolerate information missing when doing column-level lineage. Given a SQL command, SQLLineage will tell you its source and target tables, without worrying about Tokens, Keyword, Identifier and all the jagons used by SQL parsers. Is there any trick that keeps the code simple? Capture and explore lineage. I. Expression: 177 """Convert cross join unnest into lateral view explode. 6k lines. Contribute to tobymao/sqlglot development by creating an account on GitHub. dname, May 18, 2023 · The sqlglot library makes this task considerably more straightforward: import sqlglot s = """ select p. It aims to be easy to use, correct, and efficient. For more details, refer to the Child and Troubleshooting issues with reports, datasets etc in PowerBI is typically not an activity for the faint of heart. py [1] has only 1. yh ke bo af cd zt qo tj ba il