Docs updated and corrected a type in the space weather window

docs/database/db_acf.md

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+# ACF
+The table contains 4 columns explained below.
+
+!!! example
+    A technical explanation on how autocorrelation function works along with a practical example is reported [HERE](../acf_analysis.md)
+
+## ACF_ID
+`INTEGER` :material-key-outline:{ title="Primary key" } :material-upload-outline:{ title="Auto-increment" }
+
+This is a unique identification number for each entry that is assigned during the creation of a new ACF. It is auto-incrementing and is not replaced in the event of deletion.
+
+## SIG_ID
+`INTEGER` :material-axis-arrow:{ title="Foreign key" }
+
+This is a direct reference to the specific signal associated with the ACF. It links to the primary key of the [Signals](db_signals.md) table that holds detailed information about the signals.
+
+## VALUE
+`FLOAT`
+
+The autocorrelation time expressed in ms.
+
+## DESCRIPTION
+`TEXT`
+
+The short description is used to explain the details about the autocorrelation value, e.g. `Frame`, `Superframe`, etc.