x-sql-client.4.5.4.source-code.queries.adoc Maven / Gradle / Ivy
= Running queries
When you don't need a transaction or run single queries, you can run queries directly on the pool; the pool
will use one of its connection to run the query and return the result to you.
Here is how to run simple queries:
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{@link examples.SqlClientExamples#queries01(io.vertx.sqlclient.SqlClient)}
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== Prepared queries
You can do the same with prepared queries.
The SQL string can refer to parameters by position, using the database syntax {PREPARED_PARAMS}
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{@link examples.SqlClientExamples#queries02(io.vertx.sqlclient.SqlClient)}
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Query methods provides an asynchronous {@link io.vertx.sqlclient.RowSet} instance that works for _SELECT_ queries
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{@link examples.SqlClientExamples#queries03(io.vertx.sqlclient.SqlClient)}
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or _UPDATE_/_INSERT_ queries:
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{@link examples.SqlClientExamples#queries04(io.vertx.sqlclient.SqlClient)}
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The {@link io.vertx.sqlclient.Row} gives you access to your data by index
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{@link examples.SqlClientExamples#queries05(io.vertx.sqlclient.Row)}
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CAUTION: Column indexes start at 0, not at 1.
Alternatively, data can be retrieved by name:
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{@link examples.SqlClientExamples#queries06(io.vertx.sqlclient.Row)}
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The client will not do any magic here and the column name is identified with the name in the table regardless of how your SQL text is.
You can access a wide variety of of types
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{@link examples.SqlClientExamples#queries07(io.vertx.sqlclient.Row)}
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You can use cached prepared statements to execute one-shot prepared queries:
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{@link examples.SqlClientExamples#queries09(io.vertx.sqlclient.SqlClient, SqlConnectOptions)}
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You can create a `PreparedStatement` and manage the lifecycle by yourself.
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{@link examples.SqlClientExamples#queries10(io.vertx.sqlclient.SqlConnection)}
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ifndef::batching-unsupported[]
== Batches
You can execute prepared batch
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{@link examples.SqlClientExamples#queries08(io.vertx.sqlclient.SqlClient)}
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endif::[]