A WHERE clause restricts the rows a SQL statement returns or changes. Add a condition to target only matching records instead of the whole table. section 8.2.4
Where clause
A WHERE clause is a SQL query component that restricts affected or returned rows according to a condition.
How Build Python Web Apps with Streamlit covers it
- How deep it goes
- Demonstrates equality, LIKE, AND, and identifier-based filtering without detailing query planning or optimization.
- Examples
- Uses Alice’s fox haiku, haiku identifier 1, and haiku identifier 2 as filtering examples.
- What it assumes
- Assumes familiarity with SQL statements, tables, columns, and the haikus table schema.
- What you can do after
- Apply it via PostgreSQL to retrieve, update, or delete specifically matching rows.
- How it connects
- Connects SQL filtering with SELECT, UPDATE, DELETE, AND, LIKE, and table columns.
Also explained in
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Learn SQL in a Month of LunchesA WHERE clause is the SQL clause that restricts query results by requiring rows to satisfy one or more conditions.
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ScyllaDB in ActionA WHERE clause is a query-language clause that restricts returned or affected rows according to a condition.
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Kafka Streams in Action, Second EditionA WHERE clause is an SQL query clause that restricts returned records to those satisfying a Boolean condition.
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Logs and TelemetryA WHERE clause is a query construct that retains records satisfying a predicate over event values.
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Grokking Relational Database DesignA WHERE clause is an SQL clause that restricts query results to rows satisfying a predicate.
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Practical Automation with PowerShell: Effective scripting from the console to the cloudA where clause is the SQL query clause that restricts returned rows according to conditions on column values.
Compare how 7 books explain where clause →
Related concepts
- SQLpart of · SQL is a standardized declarative language for defining, querying, and manipulating data in relational database systems.
- filteringused by · Filtering is the operation of selecting or excluding items from a collection according to specified criteria.
- having clausecontrasts with · A HAVING clause is a SQL clause that filters groups or aggregate results according to a condition.
- order by clauseuses · An ORDER BY clause specifies the ordering of query results according to one or more expressions, fields, or sort directions.
- joinalternative to · A join is an operation that combines records or rows from multiple data sources according to specified matching conditions or relationships.
This explainer was generated by Manning's knowledge graph from the text of Build Python Web Apps with Streamlit. The section links point to the parts of the book it draws on.